Category: Precision Oncology

TUKYSA® Plus KADCYLA® in Advanced HER2-Positive Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. It is estimated that in the USA, approximately 310,720 new cases of female breast cancer will be diagnosed in 2024, and about 42,250 individuals will die of the disease, largely due to metastatic recurrence.

The HER or erbB family of receptors consist of HER1, HER2, HER3 and HER4. Approximately 15-20% of invasive breast cancers overexpress HER2/neu oncogene, which is a negative predictor of outcomes without systemic therapy. Patients with HER2-positive metastatic breast cancer are often treated with anti-HER2 targeted therapy along with chemotherapy, irrespective of hormone receptor status, and this has resulted in significantly improved treatment outcomes. HER2-targeted therapies include HERCEPTIN® (Trastuzumab), TYKERB® (Lapatinib), PERJETA® (Pertuzumab), KADCYLA® (ado-Trastuzumab emtansine, T-DM1), ENHERTU® (Trastuzumab deruxtecan) and MARGENZA® (Margetuximab). Dual HER2 blockade with HERCEPTIN® and PERJETA®, given along with chemotherapy (with or without endocrine therapy), as first line treatment, in HER2-positive metastatic breast cancer patients, was shown to significantly improve Progression Free Survival (PFS) as well as Overall Survival (OS). The superior benefit with dual HER2 blockade has been attributed to differing mechanisms of action and synergistic interaction between HER2 targeted therapies. Patients progressing on Dual HER2 blockade often receive KADCYLA® which results in an Objective Response Rate (ORR) of 44% and a median PFS of 9.6 months, when administered after HERCEPTIN® and a Taxane.

With advances in systemic therapies for this patient population, the incidence of brain metastases as a sanctuary site has increased. Approximately 50% of patients with HER2-positive metastatic breast cancer develop brain metastases. However, systemic HER2-targeted agents, including Tyrosine Kinase Inhibitors, as well as chemotherapy have limited antitumor activity in the brain. Local therapeutic interventions for brain metastases include neurosurgical resection and Stereotactic or Whole-Brain Radiation Therapy. There is a high unmet need for systemic treatment options to treat established brain metastases and reduce the risk for progression in the Central Nervous System (CNS).

TUKYSA® (Tucatinib) is an oral Tyrosine Kinase Inhibitor that is highly selective for the kinase domain of HER2 with minimal inhibition of Epidermal Growth Factor Receptor. In the HER2CLIMB international, randomized, double-blind, placebo-controlled trial, a combination of TUKYSA® plus HERCEPTIN® and XELODA® (Capecitabine) was compared with placebo plus HERCEPTIN® and XELODA®. TUKYSA® combination significantly improved Progression Free and Overall Survival in heavily pretreated patients, including those with brain metastases.

The HER2CLIMB-02 trial is a randomized, double-blind, placebo-controlled Phase III trial conducted to evaluate the efficacy and safety of the combination of TUKYSA® and KADCYLA® in patients with metastatic HER2-positive breast cancer, particularly those with brain metastases. This study focused on patients with brain metastases, given the limited options for managing breast cancer brain metastases. In this study, 463 patients (N=463) with unresectable locally advanced or metastatic HER2-positive breast cancer were randomly assigned in a 1:1 ratio to receive either 21-day cycles of either TUKYSA® at 300 mg orally twice a day and KADCYLA® 3.6 mg/kg IV every 3 weeks (N=228) or KADCYLA® and placebo (N=235). Both treatment groups were well balanced. The median age was 55 years, eligible patients had been previously treated with HERCEPTIN® and a Taxane in any setting, and trial entry criteria included enrollment of previously treated, stable, progressing, or untreated brain metastases not requiring immediate local therapy. Approximately 40% of all patients had baseline active or stable brain metastasis, and the researchers noted that this was the second large trial, prospectively designed to evaluate systemic therapy in patients with brain metastases. The Primary endpoint was Progression Free Survival (PFS).

At a median follow up was 24.4 months, the combination of TUKYSA® plus KADCYLA® showed a significant improvement in median PFS compared to KADCYLA® alone. The median time to disease progression or death was 9.5 months with TUKYSA® plus KADCYLA® versus 7.4 months with KADCYLA® alone, suggesting a 24% reduction in the risk of disease progression or death with the combination treatment. Among patients with brain metastasis at baseline, the median time to disease progression or death was 7.8 months with the TUKYSA® plus KADCYLA® combination versus 5.7 months with KADCYLA® alone, suggesting a 36% reduction in the risk of disease progression or death with the combination. Further, patients in the TUKYSA® plus KADCYLA® group had a higher Objective Response Rate compared to the control arm (42% versus 36.1%). Overall survival data were immature at the time of this analysis. The combination treatment group reported more treatment related adverse events which included nausea, diarrhea, fatigue and liver function abnormalities.

It was concluded that the combination of TUKYSA® and KADCYLA® demonstrated a statistically significant improvement in Progression Free Survival, compared to KADCYLA® alone, supporting its efficacy in patients with HER2-positive metastatic breast cancer. This study was prospectively designed to evaluate novel systemic therapies in patients with brain metastases, and findings from this study suggested that the combination of TUKYSA® and KADCYLA® could be a favorable treatment option, especially for patients with active or progressing brain metastases. It should be noted that this study did not directly compare the experimental regimen of TUKYSA® and KADCYLA® with other established regimens like TUKYSA® plus HERCEPTIN® and XELODA® or regimens containing ENHERTU®.

HER2CLIMB-02: randomized, double-blind phase 3 trial of tucatinib and trastuzumab emtansine for previously treated HER2-positive metastatic breast cancer. Hurvitz SA, Loi S, O’Shaughnessy J, et al. Presented at the 2023 San Antonio Breast Cancer Symposium; December 5-9, 2023; San Antonio, TX. Session GS01-10.

Sotorasib plus Panitumumab in Refractory Colorectal Cancer with Mutated KRAS G12C

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SUMMARY: Colorectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 153,020 new cases of CRC were diagnosed in the United States in 2023 and about 52,550 patients died of the disease. The lifetime risk of developing CRC is about 1 in 23.

Approximately 15-25% of the patients with CRC present with metastatic disease at the time of diagnosis (synchronous metastases) and 50-60% of the patients with CRC will develop metastatic disease during the course of their illness. First line treatment of metastatic CRC includes Oxaliplatin or Irinotecan, in combination with a Fluoropyrimidine and Leucovorin (FOLFOX or FOLFIRI respectively), along with a VEGF targeting agent such as Bevacizumab or EGFR targeting agents such as Cetuximab and Panitumumab. Patients with Stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to EGFR targeted therapy. Patients who progress following these therapies are considered to have refractory disease. These patients sometimes are rechallenged with previously administered chemotherapeutic agents, but often receive STIVARGA® (Regorafenib), an oral multikinase inhibitor with antiangiogenic activity, or LONSURF® (a fixed dose combination of Trifluridine and Tipiracil). These therapies however have shown limited efficacy.

The KRAS (Kirsten rat sarcoma viral oncogene homologue) proto-oncogene encodes a protein that is a member of the small GTPase super family. The KRAS gene provides instructions for making the KRAS protein, which is a part of a signaling pathway known as the RAS/MAPK pathway. By relaying signals from outside the cell to the cell nucleus, the protein instructs the cell to grow, divide and differentiate. KRAS gene is in the Ras family of oncogenes, which also includes two other genes, HRAS and NRAS. When mutated, oncogenes have the potential to change normal cells cancerous. KRAS is the most frequently mutated oncogene in human cancers and are often associated with resistance to targeted therapies and poor outcomes. The KRAS G12C mutation occurs in approximately 12-15% of Non Small Cell Lung Cancers (NSCLC) and in 3-5% of colorectal cancers and other solid cancers. G12C is a single point mutation with a Glycine-to-Cysteine substitution at codon 12. This substitution favors the activated state of KRAS, amplifying signaling pathways that lead to oncogenesis. Currently, no targeted therapies driven by a positive-selection biomarker are approved specifically for the treatment of patients with KRAS-mutated colorectal cancer.

Sotorasib (LUMAKRAS®) is a small molecule that specifically and irreversibly inhibits KRAS G12C protein and traps KRAS G12C in the inactive GDP-bound state, thus blocking downstream proliferation and survival signaling. Unlike the efficacy of single-agent KRAS G12C inhibitors in Non Small Cell Lung Cancer with KRAS G12C mutation, KRAS G12C inhibition alone has limited activity in patients with colorectal cancer. This has been attributed to upstream reactivation of the Epidermal Growth Factor Receptor (EGFR) pathway resulting in treatment-induced resistance, following selective inhibition of KRAS G12C. However, dual KRAS G12C and EGFR blockade can overcome treatment resistance in patients with colorectal cancer with KRAS G12C mutation. In the CodeBreaK 101 Phase 1b trial involving patients with chemorefractory colorectal cancer with mutated KRAS G12C, the Response Rate was 30% with Sotorasib plus Panitumumab, as compared with 9.7% with Sotorasib monotherapy.

CodeBreaK 300 trial is an international, multicenter, open-label, randomized, active-controlled Phase III study, conducted to evaluate the efficacy and safety of two different doses of Sotorasib (960 mg and 240 mg) in combination with Panitumumab as compared with the investigator’s choice of standard-care therapy (Trifluridine-Tipiracil or Regorafenib) in patients with chemorefractory metastatic colorectal cancer with KRAS G12C mutation. A lower dose of Sotorasib 240 mg orally once daily was tested in this study because of the nonlinear pharmacokinetic properties of Sotorasib. A total of 160 patients were randomly assigned in a 1:1:1 ratio to receive Sotorasib 960 mg orally once daily plus Panitumumab 6 mg/kg IV every 2 weeks (the 960 mg Sotorasib/Panitumumab group; N=53), Sotorasib 240 mg orally once daily plus Panitumumab (the 240 mg Sotorasib/Panitumumab group; N=53), with each treatment cycle repeating every 28 days, or the investigator’s choice of standard of care therapy which could be either Trifluridine-Tipiracil 35 mg/m2 (up to a maximum of 80 mg per dose) orally twice daily on days 1-5 and days 8-12 every 28 days, or Regorafenib 160 mg orally once daily for the first 21 days of each 28-day cycle (N=54). Treatment continued until disease progression or unacceptable toxicities. The median age was 61 years and majority of patients had more than 2 or more lines of previous anti-cancer therapy. KRAS G12C mutation was confirmed by prospective central molecular testing. Randomization was stratified according to previous use of antiangiogenic therapy, the time from initial diagnosis of metastatic disease to randomization and ECOG-PS. The Primary end point was Progression Free Survival (PFS) as assessed by Blinded Independent Central Review (BICR). Key Secondary end points included Overall Survival (OS) and Objective Response Rate (ORR).

After a median follow up of 7.8 months, both Sotorasib combinations (960 mg and 240 mg) plus Panitumumab demonstrated significantly longer PFS compared to standard of care therapy. The median PFS was 5.6 months and 3.9 months in the 960 mg Sotorasib/Panitumumab and 240 mg Sotorasib/Panitumumab groups, respectively, as compared with 2.2 months in the standard of care group (HR for 960 mg group=0 49; P=0.006) (HR for 240 mg group=0.58; P=0.03). The improvement in PFS was observed across key subgroups, including tumor sideness/primary tumor location, prior lines of therapy, and the presence or absence of liver metastases. The Objective Response Rate was 26.4%, 5.7%, and 0% in the 960 mg Sotorasib/Panitumumab, 240 mg Sotorasib/Panitumumab, and standard of care groups, respectively. Overall survival data is immature. While this trial was not powered to compare the two Sotorasib/Panitumumab groups directly, the 960-mg dose appeared to yield more clinically significant benefits than the 240-mg dose, across all efficacy endpoints, without additional toxic effects. Grade 3 or higher treatment-related adverse events occurred in 35.8%, 30.2%, and 43.1% of patients, respectively. Skin-related toxic effects and hypomagnesemia were the most common adverse events observed with Sotorasib/Panitumumab.

It was concluded from this study that both doses of Sotorasib (960 mg and 240 mg) in combination with Panitumumab resulted in significantly longer Progression Free Survival and a higher incidence of Response Rate than standard treatment. Ongoing analysis and longer follow up will provide additional insights into Overall Survival outcomes.

Sotorasib plus Panitumumab in Refractory Colorectal Cancer with Mutated KRAS G12C. Fakih MG, Salvatore L, Esaki T, et al. N Engl J Med 2023;389:2125-2139.

FDA Approves AUGTYRO® for ROS1-positive Non-Small Cell Lung Cancer

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SUMMARY: The FDA on November 15, 2023, approved AUGTYRO® (Repotrectinib) for locally advanced or metastatic ROS1-positive Non-Small Cell Lung Cancer (NSCLC). This is the first FDA approval that includes patients with ROS1-positive NSCLC who have previously received a ROS1 Tyrosine Kinase Inhibitor (TKI), in addition to patients who are TKI naïve.

Approximately 1-2% of lung adenocarcinomas harbor ROS1 gene rearrangements. ROS1 gene is located on chromosome 6q22 (long arm of chromosome 6) and plays an important role in cell growth and development. ROS1 gene fusion with another gene results in a mutated DNA sequence which then produces an abnormal protein responsible for unregulated cell growth and cancer. ROS1 gene rearrangement has been identified as a driver mutation in Non Small Cell Lung Cancer with adenocarcinoma histology. This is more common in nonsmokers or in light smokers (<10 pack years) who are relatively young (average age of 50 years), and thus share similar characteristics with ALK-positive patients. ROS1 mutations have been also been associated with Cholangiocarcinoma (Bile duct cancer) and Glioblastoma multiforme. ROS1 rearrangements are mutually exclusive with other oncogenic mutations found in NSCLC such as EGFR mutations, KRAS mutations and ALK rearrangement. The presence of a ROS1 rearrangement can be detected by Fluorescence In Situ Hybridization (FISH), ImmunoHistoChemistry (IHC), Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) and Next Generation-Sequencing. There are currently two FDA-approved treatment options for ROS1-positive metastatic NSCLC- Crizotinib and Entrectinib.

Repotrectinib is a next-generation TKI targeting ROS1 or NTRK-positive locally advanced or metastatic solid tumors, including NSCLC. Repotrectinib was designed to improve durability of response and with favorable properties to enhance intracranial activity.

The FDA approval was based on the results of the TRIDENT-1 global, multicenter, single-arm, Phase I/II, open-label, multi-cohort clinical trial, designed to evaluate the safety, tolerability, pharmacokinetics, and anti-tumor activity of Repotrectinib, in patients with advanced solid tumors, including locally advanced or metastatic NSCLC. Phase I component of the trial evaluated the safety and pharmacokinetics, whereas in the Phase II component of the study included six distinct expansion cohorts, including TKI-naïve and TKI-pretreated patients with ROS1-positive locally advanced or metastatic NSCLC and NTRK-positive advanced solid tumors. Eligibility requirements included locally advanced or metastatic solid tumors harboring ROS1 or NTRK1-3 gene fusions. Patients with asymptomatic CNS metastases were allowed. Patients received Repotrectinib 160 mg once daily, orally for 14 days, followed by 160 mg twice daily until disease progression or unacceptable toxicities. The Primary endpoint was Overall Response Rate (ORR) as assessed by Blinded Independent Central Review (BICR), and Secondary endpoints included Duration of Response (DOR), Progression Free Survival (PFS), Overall Survival (OS) and Clinical Benefit Rate (CBR). The efficacy was evaluated in ROS1 TKI-naïve patients (N=71) who received up to one prior line of platinum-based chemotherapy and/or immunotherapy, and in patients who received one prior ROS1 TKI with no prior platinum-based chemotherapy or immunotherapy (N=56).

In TKI-naïve patients with median follow-up of 24.0 months, the confirmed Objective Response Rate by BICR was 79%, median Duration of Response was 34.1 months and PFS was 35.7 months. In patients with measurable brain metastases at baseline (N=9), intracranial ORR per BICR was 89% and these responses were prolonged.

In patients who received one prior ROS1 TKI with no prior chemotherapy or immunotherapy, at a median follow-up of 21.5 months, the confirmed Objective Response Rate by BICR was 38%, median Duration of Response was 14.8 months and PFS was 9.0 months. In this subset of patients with measurable brain metastases at baseline (N=13), intracranial ORR per BICR was 38%.

The most common adverse reactions were fatigue, dizziness, dyspnea, dysgeusia, peripheral neuropathy, constipation, ataxia, cognitive disorders, and muscular weakness.

It was concluded that the TRIDENT-1 trial demonstrated the efficacy of Repotrectinib in both, TKI-naïve and previously treated patients, showcasing high response rates and durable outcomes. These data will provide physicians with valuable insights into the clinical benefits with Repotrectinib , paving the way for its potential adoption as a new standard of care, in the treatment of ROS1-positive NSCLC. TRIDENT-1 trial is ongoing to assess long term outcomes and additional endpoints across patient populations with ROS1-positive locally advanced or metastatic NSCLC, and NTRK-positive advanced solid tumors.

Repotrectinib in patients with ROS1 fusion-positive (ROS1+) NSCLC: Update from the pivotal phase 1/2 TRIDENT-1 trial. Cho BC, Camidge DR, Lin JJ, et al. Presented at the IASLC 2023 World Conference on Lung Cancer; September 10-12, 2023; Singapore. Abstract OA03.06.

Biomarker Driven ELAHERE® in FR alpha-Positive, Platinum-Resistant Ovarian Cancer

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SUMMARY: It is estimated that in the United States, approximately 19,710 women will be diagnosed with ovarian cancer in 2023, and 13,270 women will die of the disease. Ovarian cancer ranks fifth in cancer deaths among women, and accounts for more deaths than any other cancer of the female reproductive system. Approximately 75% of the ovarian cancer patients are diagnosed with advanced disease. About 85% of all ovarian cancers are epithelial in origin, and 70% of all epithelial ovarian cancers are High-Grade serous adenocarcinomas. Patients with newly diagnosed advanced ovarian cancer are often treated with platinum-based chemotherapy following primary surgical cytoreduction. Approximately 70% of these patients will relapse within the subsequent 3 years and are incurable, with a 5-year Overall Survival (OS) rate of about 20-30%. Treatment options for patients with platinum-resistant ovarian cancer are limited, and patients are often treated with single-agent chemotherapy, with an Overall Response Rate (ORR) of between 4% and 13%, short duration of response, and significant toxicities.

Approximately 35-40% of ovarian cancer patients express high levels of Folate Receptor alpha (FR alpha), and this expression correlates with advanced stages of disease and more malignant phenotypes. There is limited expression of Folate Receptor alpha in normal tissues and is limited to the choroid plexus, proximal renal tubules, placenta, and endometrium. Testing for Folate Receptor alpha can be performed on fresh or archived tissue.

ELAHERE® (Mirvetuximab soravtansine-gynx) is a first-in-class Antibody Drug Conjugate (ADC), directed against FR alpha, a cell-surface protein highly expressed in ovarian cancer. It is comprised of a Folate Receptor alpha-binding antibody, cleavable linker, and the maytansinoid payload DM4, which is a potent tubulin inhibitor, disrupting microtubule formation, and thereby designed to kill the targeted cancer cells. Microtubules are major components of the cytoskeleton that give shape and structure to cells. ELAHERE® is the first FDA approved ADC for platinum-resistant disease. In the single-arm SORAYA trial, ELAHERE® demonstrated an ORR of 31.7% and median Duration of Response of 6.9 months, in patients with platinum-resistant ovarian cancer, and prior Bevacizumab exposure. These response rates were consistently seen regardless of the number of prior therapies or the use of a prior PARP inhibitor. As a result, the FDA in November 2022 granted accelerated approval to ELAHERE®.

MIRASOL is a confirmatory randomized Phase III trial, conducted to evaluate the efficacy and safety of ELAHERE® versus Standard-of-Care chemotherapy, in patients with pretreated, platinum-resistant ovarian, peritoneal, or fallopian tube cancer, whose tumors express high levels of FR alpha. In this study, 453 eligible patients (N=453) were randomized 1:1 to receive ELAHERE® 6 mg/kg (based on adjusted ideal body weight) IV infusion once every three weeks, until disease progression or unacceptable toxicity (N=227), or investigators choice of single-agent chemotherapy – Paclitaxel, Pegylated Liposomal Doxorubicin, or Topotecan (N=226)). Both treatment groups were well balanced. Approximately 13% of patients had BRCA mutations, 14% of patients had one prior line of therapy, 39% had two prior lines and 47% had three prior lines of therapy. About 62% received prior Bevacizumab and 55% received prior therapy with PARP inhibitors. The Primary efficacy endpoint was Progression Free Survival (PFS). Secondary endpoints included Overall Response Rate (ORR), Overall Survival (OS), and Patient-Reported Outcomes in hierarchical order, as well as Safety and tolerability. The median follow up was 13.1 months.

This study met its Primary and key Secondary endpoints with statistically significant improvement in PFS, ORR and OS. The PFS in the ELAHERE® group was 5.62 months compared to 3.98 months in the chemotherapy group (HR=0.65; P<0.0001). The ORR was also higher in the ELAHERE® group at 42% compared with 16% in the chemotherapy group (P<0.0001). The median Overall Survival rate was 16.46 months among patients who received ELAHERE® compared with 12.75 months among those who received single-agent chemotherapy (HR=0.67; P=0.005). The PFS and OS outcomes favored the ELAHERE® group, irrespective of prior exposure to Bevacizumab. Treatment with ELAHERE® was associated with a lower rate of Grade 3 or more Adverse Events and a lower discontinuation rate (9% compared with 16% for the chemotherapy group). The most common adverse reactions including laboratory abnormalities associated with ELAHERE® were vision impairment, keratopathy, fatigue, nausea, peripheral neuropathy, increase in ALT and AST and cytopenias. Product labeling includes a boxed warning for ocular toxicity. The ocular events were reversible and primarily included low-grade blurred vision and keratopathy, which were managed with protocol-defined dose modifications. Approximately 60% of patients with symptoms had resolution prior to their next cycle of treatment, and less than 1% of patients discontinued therapy due to an ocular event.

It was concluded that treatment with ELAHERE® demonstrated a statistically significant improvement in Progression Free Survival and Overall survival, compared to chemotherapy, in patients with platinum-resistant ovarian cancer and high FR alpha expression, independent of Bevacizumab use, and may be the new standard-of-care for this patient group. ELAHERE® is the first FDA-approved Antibody Drug Conjugate and biomarker directed therapy for ovarian cancer, since the approval of PARP inhibitors.

Mirvetuximab Soravtansine in FRα-Positive, Platinum-Resistant Ovarian Cancer. Moore KN, Angelergues A, Konecny GE, et al. N. Engl J Med 2023;389:2162-2174

FDA Approves TRUQAP® with Fulvestrant for Advanced Breast Cancer

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SUMMARY: The FDA on November 16, 2023, approved Capivasertib (TRUQAP®) with Fulvestrant for adult patients with Hormone Receptor-positive (HR-positive), Human Epidermal growth factor Receptor 2-negative (HER2-negative) locally advanced or metastatic breast cancer with one or more PIK3CA/AKT1/PTEN-alterations, as detected by an FDA-approved test, following progression on at least one endocrine-based regimen in the metastatic setting or recurrence on or within 12 months of completing adjuvant therapy. FDA also approved the FoundationOne® CDx assay as a companion diagnostic device to identify patients with breast cancer for treatment with Capivasertib with Fulvestrant.

Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. It is estimated that approximately 300,590 new cases of breast cancer will be diagnosed in 2023 and about 43,700 individuals will die of the disease, largely due to metastatic recurrence. Breast cancer is the second leading cause of cancer death in women, in the U.S. About 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors, and Hormone Receptor-positive (HR-positive), HER2-negative breast cancer is the most frequently diagnosed molecular subtype. The most common subtype of metastatic breast cancer is HR-positive, HER2-negative breast cancer (65% of all metastatic breast tumors), and these patients are often treated with anti-estrogen therapy as first line treatment. However, resistance to hormonal therapy occurs in a majority of the patients, with a median Overall Survival (OS) of 36 months. With the development of Cyclin Dependent Kinases (CDK) 4/6 inhibitors, endocrine therapy plus a CDK4/6 inhibitor is the mainstay, for the management of HR-positive, HER2-negative metastatic breast cancer, as first line therapy. Even with this therapeutic combination, most patients will eventually experience disease progression due to resistance to endocrine therapy. A therapy overcoming endocrine resistance is an area of active research in the breast cancer space.

The P13K/Akt pathway is a growth-regulating cellular signaling pathway, which in many human cancers is overactivated. Inhibition of the PI3K/Akt signaling pathway leads to inhibition of cell proliferation and induction of apoptosis in tumor cells. A wide range of solid and hematological malignancies show dysregulated PI3K/AKT/mTOR/PTEN signaling due to mutations in the genes involved. Overactivation of the PI3K-AKT-PTEN signaling pathway occurs in approximately 50% of HR-positive, HER2-negative breast cancers by means of activating mutations in PIK3CA and AKT1 and inactivating alterations in PTEN. These alterations may be present at the time of cancer recurrence, and can also be acquired following previous treatment including with CDK4/6 inhibitors. Further, AKT signaling may also be activated in the absence of genetic alterations in patients with endocrine resistance.

Capivasertib is a novel, first-in-class, orally bioavailable small molecule inhibitor of the serine/threonine protein kinase AKT (protein kinase B), with potential antineoplastic activity. It is a potent, selective ATP-competitive inhibitor of all three AKT isoforms (AKT1/2/3). By targeting AKT, the key node in the PIK3/AKT signaling network, Capivasertib potentially may be used as monotherapy or combination therapy, for a variety of human cancers. In the Phase II FAKTION trial, Capivasertib in combination with Fulvestrant significantly improved Progression Free and Overall Survival as compared with Fulvestrant alone, among postmenopausal women with HR-positive advanced breast cancer, who had previously received endocrine therapy. The researchers conducted the CAPItello-291 trial to determine whether the addition of Capivasertib to Fulvestrant would improve outcomes in patients with HR-positive breast cancer whose tumors had developed resistance to an Aromatase Inhibitor and CDK4/6 inhibitor.

CAPItello-291 is a randomized, double-blind Phase III trial in which 708 adult patients with histologically confirmed HR-positive, HER2-low or negative breast cancer, whose disease has recurred or progressed during or after Aromatase Inhibitor therapy, with or without a CDK4/6 inhibitor, were enrolled. Patients were randomly assigned 1:1 to receive either the Capivasertib plus Fulvestrant (N=355) arm or the placebo plus Fulvestrant arm (N=353). Patients in the study group received Capivasertib 400 mg orally twice daily for 4 days on and 3 days off along with Fulvestrant 500 mg IM on days 1 and 15 during cycle 1, then every 4 weeks thereafter. The present dosing of Capivasertib was chosen based on tolerability and the degree of target inhibition in early phase trials. The control group received matched placebo along with Fulvestrant. Patients received therapy until disease progression or unacceptable toxicity. In this trial, patients could have received up to two prior lines of endocrine therapy and up to 1 line of chemotherapy for locally advanced or metastatic disease. Approximately 40% of tumors (N=289) had PI3K/AKT/PTEN alterations. Both treatment groups were well balanced. Stratification factors included liver metastases and prior CDK 4/6 inhibitor. The dual Primary endpoints were Progression Free Survival (PFS) in the overall patient population and in a subgroup of patients whose tumors have qualifying alterations in the PIK3CA, AKT1 or PTEN genes. Secondary endpoints included Overall Survival (OS) and Objective Response Rate (ORR).

The trial met both Primary endpoints, improving PFS in the overall patient population and in a prespecified biomarker subgroup of patients whose tumors had qualifying alterations in the AKT pathway genes. In the overall trial population, patients treated with Capivasertib plus Fulvestrant had a median PFS of 7.2 months, compared to 3.6 months in patients treated with placebo plus Fulvestrant (HR=0.60; P<0.001). This amounted to a 40% lower risk of disease progression among patients who received Capivasertib plus Fulvestrant. Among patients with AKT pathway mutations treated with Capivasertib plus Fulvestrant, the median PFS was 7.3 months versus 3.1 months in the placebo group (HR=0.50; P<0.001), reducing the risk of disease progression or death by 50%, versus placebo plus Fulvestrant. An exploratory analysis of PFS in the 313 patients whose tumors did not have a PIK3CA, AKT1 or PTEN-alteration showed a HR of 0.79, suggesting that the difference in the overall population was primarily attributed to the results seen in the population of patients whose tumors have PIK3CA, AKT1 or PTEN-alteration. The benefit from Capivasertib was consistent across key clinically relevant subgroups, including patients previously treated with CDK4/6 inhibitor and patients with liver metastases.
The Objective Response Rate in the overall trial population was 22.9% among patients treated with Capivasertib plus Fulvestrant compared with 12.2% for patients treated with placebo plus Fulvestrant, and was 28.8% and 9.7% respectively in the biomarker altered population. Although the Overall Survival data were immature at the time of the analysis, early data are encouraging and follow up is ongoing. The most frequent Grade 3 or higher toxicities occurring in 5% or more of patients were diarrhea (9.3%) and rash (12.1%). Treatment discontinuation due to adverse events was 13% among patients who received Capivasertib plus Fulvestrant versus 2.3% among patients who received placebo plus Fulvestrant.

It was concluded that a combination of Capivasertib plus Fulvestrant is a new treatment option with significantly improved Progression Free Survival, in patients who have Hormone Receptor–positive/HER2-negative advanced breast cancer, who had progressed on, or have become resistant to endocrine therapies and CDK4/6 inhibitors.

Capivasertib in Hormone Receptor–Positive Advanced Breast Cancer. Turner N, Oliveria M, Howell SJ, et al., for the CAPItello-291 Study Group. N Engl J Med 2023; 388:2058-2070.

Osimertinib Plus Chemotherapy Superior to Osimertinib Alone in Advanced EGFR Mutated Non Small Cell Lung Cancer

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SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2023, about 238,340 new cases of lung cancer will be diagnosed and 127,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

Approximately 10-15% of Caucasian patients and 35-50% of Asian patients with Adenocarcinomas, harbor activating EGFR (Epidermal Growth Factor Receptor) mutations and 90% of these mutations are either Exon 19 deletions or L858R substitution mutation in Exon 21. Approximately 25% of patients with EGFR mutated NSCLC have brain metastases at diagnosis, increasing to approximately 40% within two years of diagnosis. The presence of brain metastases often reduces median survival to less than eight months. EGFR-Tyrosine Kinase Inhibitors (TKIs) such as TARCEVA® (Erlotinib), IRESSA® (Gefitinib) and GILOTRIF® (Afatinib), have demonstrated a 60-70% response rate as monotherapy when administered as first line treatment, in patients with metastatic NSCLC, who harbor the sensitizing EGFR mutations. However, majority of these patients experience disease progression within 9-14 months. This resistance to frontline EGFR TKI therapy has been attributed to the most common, acquired T790M “gatekeeper” point mutation in EGFR, identified in 50-60% of patients.

Osimertinib (TAGRISSO®) is a highly selective third-generation, irreversible Epidermal Growth Factor Receptor TKI, presently approved by the FDA, for the first-line treatment of patients with metastatic NSCLC, whose tumors have Exon 19 deletions or Exon 21 L858R mutations, as well as treatment of patients with metastatic EGFR T790M mutation-positive NSCLC, whose disease has progressed on or after EGFR-TKI therapy. Further, Osimertinib has higher CNS penetration and is therefore able to induce responses in 70-90% of patients with brain metastases.

In the Phase III FLAURA trial, among patients with metastatic, EGFR-mutant NSCLC, first-line treatment with Osimertinib significantly improved median Overall Survival, compared with Erlotinib and Gefitinib, and Osimertinib therefore has been the preferred regimen in this patient group. The FLAURA2 trial builds on the favorable results observed in the Phase III FLAURA trial.
FLAURA2 is a randomized, open-label, multi-center, global, ongoing Phase III trial, in which 557 enrolled treatment naïve patients (N=557), with nonsquamous locally advanced (Stage IIIB-IIIC) or metastatic EGFR mutated NSCLC, were randomly assigned 1:1 to receive Osimertinib plus chemotherapy (N=279) or Osimertinib monotherapy (N=278). Patients in the combination group received Osimertinib 80 mg oral tablets once daily in combination with chemotherapy consisting of Pemetrexed 500 mg/m2 IV plus Cisplatin 75 mg/m2 IV or Carboplatin (AUC5), every three weeks for four cycles, followed by Osimertinib with Pemetrexed maintenance every three weeks. The median patient age was 62 years, approximately 62% were women and 64% were Asian. About 61% had Exon 19 deletion and 38% had L858R substitution mutation in Exon 21, 40% had CNS metastases and 53% had extrathoracic metastases. Approximately 76% of patients completed four cycles of platinum therapy. The Primary end point was investigator-assessed Progression Free Survival (PFS). Secondary endpoints included Overall Survival (OS), Objective Response Rate (ORR) and Safety. The median follow-up for progression-free survival was 19.5 months in the osimertinib–chemotherapy group and 16.5 months in the osimertinib group.

In this final analysis of the Primary endpoint of PFS, results from this study showed a significant improvement in PFS with the Osimertinib plus chemotherapy combination versus Osimertinib alone (HR=0.62; P<0.001). The median PFS was 25.5 months versus 16.7 months respectively. This represented a 38% reduction in disease progression risk, compared to Osimertinib monotherapy. The PFS benefit with Osimertinib plus chemotherapy was consistent across prespecified subgroups, including the subgroups defined according to EGFR mutation type and the presence or absence of CNS metastases at baseline. The Objective Response Rate with the combination regimen was 83%, compared to 76%, in the Osimertinib monotherapy group. The median response duration was 24 months and 15.3 months respectively. Grade 3 or higher hematologic adverse events occurred more frequently in the combination regimen group and were manageable. Data for Overall Survival were immature at the time of the analysis, and this ongoing trial will continue to assess the Secondary endpoint of Overall Survival.

The authors concluded that FLAURA2 provides compelling evidence that the addition of chemotherapy to Osimertinib in the first line treatment of nonsquamous, locally advanced or metastatic EGFR mutated NSCLC, can significantly improve outcomes, compared to Osimertinib alone, and can delay resistance to therapy and disease progression.

Osimertinib with or without Chemotherapy in EGFR-Mutated Advanced NSCLC. Planchard D, Jänne PA, Cheng Y, et al. for the FLAURA2 Investigators. N Engl J Med 2023; 389:1935-1948

Amivantamab plus Chemotherapy with and without Lazertinib after Progression on Osimertinib in Advanced Lung Cancer

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SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2023, about 238,340 new cases of lung cancer will be diagnosed and 127,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer. Approximately 10-15% of Caucasian patients and 35-50% of Asian patients with Adenocarcinomas, harbor activating EGFR mutations and 90% of these mutations are either exon 19 deletions or L858R substitution mutation in exon 21.

Epidermal Growth Factor Receptor (EGFR) plays an important role in regulating cell proliferation, survival and differentiation, and is overexpressed in a variety of epithelial malignancies. EGFR targeted Tyrosine Kinase Inhibitors (TKIs) such as Gefitinib, Erlotinib, Afatinib, Dacomitinib and Osimertinib target the EGFR signaling cascade. However, patients eventually will develop drug resistance due to new EGFR mutations. Another important cause of drug resistance to TKIs is due to the activation of parallel RTK (Receptor Tyrosine Kinase) pathways such as Hepatocyte Growth Factor/Mesenchymal-Epithelial Transition factor (HGF/MET) pathway, thereby bypassing EGFR TKI inhibitors. These patients are often treated with platinum-based chemotherapy as the next line of therapy, resulting in a median Progression Free Survival of 5 months.

Amivantamab (RYBREVANT®) is a fully-human bispecific antibody directed against EGFR and MET receptors. Amivantamab binds extracellularly and simultaneously blocks ligand-induced phosphorylation of EGFR and c-MET, inhibiting tumor growth and promoting tumor cell death. Further, Amivantamab downregulates receptor expression on tumor cells thus preventing drug resistance mediated by new emerging mutations of EGFR or c-MET. By binding to the extracellular domain of the receptor protein, Amivantamab can bypass primary and secondary TKI resistance at the active site. Amivantamab also engages effector cells such as Natural Killer cells, monocytes, and macrophages via its optimized Fc domain. Amivantamab demonstrated activity against a wide range of activating and resistance mutations in EGFR-mutated NSCLC, and in patients with MET exon 14 skip mutations, and is approved for the treatment of patients with EGFR exon 20 insertion mutations, whose disease progressed on or after platinum-based chemotherapy.

Lazertinib is a highly selective, third-generation TKI that penetrates the CNS, with demonstrated efficacy in activating EGFR mutations and acquired T790M “gatekeeper” point mutation. Combining Amivantamab with Lazertinib has been shown to provide a synergistic benefit by targeting the extracellular and catalytic EGFR domains. In early phase studies, Amivantamab plus chemotherapy and Amivantamab, Lazertinib plus chemotherapy demonstrated an Objective Response Rate of 44% and 50% in advanced and refractory NSCLC, and in patients whose disease had progressed on prior TKIs, respectively.

MARIPOSA-2 is a global, randomized, Phase 3 trial, conducted to assess the efficacy and safety of Amivantamab plus chemotherapy and Amivantamab, Lazertinib plus chemotherapy versus chemotherapy alone, in patients with EGFR-mutated advanced NSCLC, whose disease had progressed on or after Osimertinib monotherapy. Amivantamab is a large molecule and was not expected to readily cross the blood-brain barrier. This was one of the main reasons for the addition of Lazertinib, a known CNS-active TKI, to Amivantamab plus chemotherapy. A total of 657 patients (N=657) with EGFR-mutated (exon 19 deletions or L858R substitution mutations) locally advanced or metastatic NSCLC, after disease progression on Osimertinib, were randomized 2:2:1 to receive either Amivantamab along with Lazertinib and chemotherapy (N=263), chemotherapy alone (N=263), or Amivantamab plus chemotherapy (N=131). Patients received Amivantamab 1400 mg IV (1750 mg for body weight 80 kg or greater) weekly for the first 4 weeks, then 1750 mg (2100 mg for body weight 80 kg or greater) every 3 weeks starting at cycle 3 (week 7). The first Amivantamab infusion was split over 2 days, with 350 mg IV on cycle 1, day 1 and the remainder on cycle 1, day 2. Lazertinib was administered at 240 mg orally daily. Chemotherapy consisted of Carboplatin AUC5 IV, starting on day 1 every 3 weeks for the first 4 cycles along with Pemetrexed 500 mg/m2 IV every 3 weeks until disease progression. The median age was 62 years, 48% of patients were Asian, about 45% of patients had a history of brain metastases, and approximately 70% of patients had Osimertinib as first line treatment and 30% had Osimertinib as second line treatment. Randomization was stratified by Osimertinib line of therapy (first or second), race (Asian or non-Asian), and history of brain metastasis (yes or no). All three treatment groups were well balanced. The dual Primary endpoints were Progression Free Survival (PFS) of Amivantamab plus chemotherapy and Amivantamab, Lazertinib plus chemotherapy, versus chemotherapy alone. Secondary endpoints included Objective Response Rate (ORR), Duration of Response, Overall Survival (OS) and Safety.

At a median follow-up of 8.7 months, the PFS was significantly longer for Amivantamab plus chemotherapy and Amivantamab, Lazertinib plus chemotherapy versus chemotherapy alone (HR for disease progression or death=0.48 and 0.44, respectively; P<0.001 for both; median of 6.3 and 8.3 versus 4.2 months, respectively). The Objective Response Rate was significantly higher for Amivantamab plus chemotherapy and Amivantamab, Lazertinib plus chemotherapy versus chemotherapy alone (64% and 63% versus 36%, respectively; P<0.001 for both). The median intracranial PFS was 12.5 and 12.8 versus 8.3 months for Amivantamab plus chemotherapy and Amivantamab, Lazertinib plus chemotherapy versus chemotherapy alone (HR for intracranial disease progression or death=0.55 and 0.58, respectively). The researchers postulated that the mechanism by which Amivantamab improves intracranial PFS could either be through direct antitumor effects or indirectly through immune-based mechanisms. The most common adverse events with the Amivantamab combinations were cytopenias, infusion-related reactions and venous thromboembolism. The researchers recommend prophylactic anticoagulation.

It was concluded that Amivantamab plus chemotherapy, as well as Amivantamab, Lazertinib plus chemotherapy, significantly improved Progression Free Survival (PFS) and intracranial PFS, compared with chemotherapy alone, in patients with EGFR-mutated advanced NSCLC with disease progression on or after Osimertinib. The authors added that MARIPOSA-2 is the first study to demonstrate improved PFS versus chemotherapy, after disease progression on Osimertinib.

Amivantamab plus chemotherapy with and without lazertinib in EGFR-mutant advanced NSCLC after disease progression on osimertinib: Primary results from the phase 3 MARIPOSA-2 study. Passaro A, Wang J, Wang Y, et al. Annals of Oncology. 2023. DOI:https://doi.org/10.1016/j.annonc.2023.10.117

FDA Approves Ivosidenib for Myelodysplastic Syndromes

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SUMMARY: The FDA on October 24, 2023, approved Ivosidenib (TIBSOVO®) for adult patients with Relapsed or Refractory MyeloDysplastic Syndromes (MDS) with a susceptible Isocitrate DeHydrogenase-1 (IDH1) mutation, as detected by an FDA-approved test. The FDA also approved the Abbott RealTime IDH1 Assay as a companion diagnostic device to select patients for Ivosidenib.

It is estimated that in the US approximately 13,000 people are diagnosed with MyeloDysplastic Syndromes (MDS) each year. The prevalence has been estimated to be from 60,000 to 170,000 in the US. MyeloDysplastic Syndromes are a heterogenous group of stem cell disorders characterized by marrow failure resulting in cytopenias, mainly symptomatic anemia, with associated cytogenetic abnormalities, and abnormal cellular maturation with morphologic changes in clonal cells. Majority of the individuals diagnosed with MDS are 65 years or older and die as a result of infection and/or bleeding, consequent to bone marrow failure. About a third of patients with MDS develop Acute Myeloid Leukemia (AML).

The International Prognostic Scoring System (IPSS) for MDS has 4 risk groups based on Total Risk Score (Low, Intermediate-1, Intermediate-2 and High). The three prognostic factors scored to predict the course of the patient’s disease include, percentage of blast cells in the bone marrow, type of chromosomal changes in the marrow cells and number of cytopenias (anemia, neutropenia or thrombocytopenia). Patients with low-risk MDS have an indolent disease course with a median survival of about 6 years with no therapeutic intervention. Patients with intermediate and higher-risk disease however have a shorter median survival even with treatment, with approximately a third of the patients progressing to AML within 3 years.

Patients with Low-risk MDS often present with symptomatic anemia and these patients are in chronic need for RBC transfusions. These patients are treated with Erythropoiesis Stimulating Agents (ESAs) as first line therapy. ESAs such as Darbepoetin alfa and Epoetin alfa are re-engineered and recombinant DNA technology products of Erythropoietin (EPO), and they stimulate erythropoiesis by binding and activating the EPO receptor. However, transfusion-dependent patients with serum EPO levels above 200U per liter are less likely to respond to ESAs. A majority of patients with higher-risk MDS are treated with hypomethylating agents such as Azacitidine and Decitabine and these agents can favorably modify the natural history of the disease, and have been shown to improve survival. However, outcomes are poor and no therapies currently exist for patients with Isocitrate Dehydrogenase 1-mutant Relapsed or Refractory MDS, following failure on a hypomethylating agent.

Isocitrate DeHydrogenase (IDH) is a metabolic enzyme that helps generate energy from glucose and other metabolites, by catalyzing the conversion of Isocitrate to Alpha-Ketoglutarate. Alpha-ketoglutarate is required to properly regulate DNA and histone methylation, which in turn is important for gene expression and cellular differentiation. IDH mutations lead to aberrant DNA methylation and altered gene expression thereby preventing cellular differentiation, with resulting immature undifferentiated cells. IDH mutations can thus promote leukemogenesis in Acute Myeloid Leukemia and tumorigenesis in solid tumors and can result in inferior outcomes. There are three isoforms of IDH. IDH1 is mainly found in the cytoplasm, as well as in peroxisomes, whereas IDH2 and IDH3 are found in the mitochondria, and are a part of the Krebs cycle. Approximately 20% of patients with AML, 70% of patients with Low-grade Glioma and secondary Glioblastoma, 50% of patients with Chondrosarcoma, 20% of patients with Intrahepatic cholangiocarcinoma, 30% of patients with Angioimmunoblastic T-cell lymphoma and 8% of patients with Myelodysplastic syndromes/Myeloproliferative neoplasms, are associated with IDH mutations.

Ivosidenib is a first-in-class, oral, potent, targeted, small-molecule inhibitor of mutant IDH1. The FDA in 2018, approved Ivosidenib for adult patients with Relapsed or Refractory AML with a susceptible IDH1 mutation, and in 2019 approved Ivosidenib for newly diagnosed AML with a susceptible IDH1 (Isocitrate DeHydrogenase-1) mutation, in patients who are at least 75 years old or who have comorbidities that preclude the use of intensive induction.

The present FDA approval is supported by a pivotal Phase 1, open-label, multinational study, in which the safety, tolerability, and clinical activity of Ivosidenib was evaluated among patients with Relapsed or Refractory Myelodysplastic syndromes with an IDH1 mutation. In this study 18 eligible patients (N=18) received Ivosidenib 500 mg orally daily, continuous for 28-day cycles, until disease progression, unacceptable toxicity, or Hematopoietic Stem Cell Transplantation. The median treatment duration was 9.3 months. One patient underwent a Stem Cell Transplantation following Ivosidenib. IDH1 mutations were detected in peripheral blood or bone marrow by a local or central diagnostic test and confirmed retrospectively by the Abbott RealTime IDH1 Assay. The median age was 73 years and majority of patients had intermediate or high IPSS-R score at the time of screening for the study. The Primary efficacy end point was the Complete Response (CR) plus Partial Response (PR) rate. Secondary endpoints included duration of CR plus PR, duration of transfusion independence, and time to transfusion independence.

All observed responses were Complete Responses. The CR rate was 38.9%. The median time to Complete Response was 1.9 months and at the time of data cutoff, the median duration of Complete Responses was not estimable and ranged from 1.9 to 80.8+ months. Additionally, of the 9 patients who were transfusion dependent with Red Blood Cells or platelets at baseline, 67% became RBC and platelet transfusion independent during any 56-day post-baseline period. Of the 9 patients independent of both RBC and platelet transfusions at baseline, 78% remained transfusion independent during any 56-day post-baseline period. The most common adverse reactions included GI toxicities such as mucositis, diarrhea, constipation and nausea, fatigue, arthralgia, myalgia, cough, and rash. Differentiation syndrome was rare and manageable. It should be noted that Ivosidenib can also cause QTc prolongation.

It was concluded from this study that Ivosidenib induced durable remissions including a substantial proportion of Complete Remissions with an acceptable safety profile, in patients with Relapsed or Refractory Myelodysplastic syndromes with an IDH1 mutation. Further, a significant proportion of patients became or remained transfusion independent. This is the first targeted therapy approved for this indication.

UPDATED SUBSTUDY RESULTS FOR IVOSIDENIB IN IDH1-MUTANT RELAPSED/REFRACTORY MYELODYSPLASTIC SYNDROME. Dinardo C, Roboz G, Watts JM, et al. Hemasphere. 2023 Aug; 7(Suppl): e75740ab. DOI: 10.1097/01.HS9.0000969800.75740.ab.

Single Blood Test for Multi-Cancer Early Detection

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SUMMARY: The American Cancer Society estimates that in 2023, 1,958,310 new cancer cases and 609,820 cancer deaths are projected to occur in the United States. Although cancer mortality rates continue to decline with advances in treatment, improving early detection can reduce disease and treatment-related morbidity, improve treatment outcomes, quality of life and reduce financial burden both for the patient as well as the society as a whole. Currently the USPSTF (Unites States Preventive Services Task Force) and ACS (American Cancer Society) recommend screening for breast, cervical, colorectal, and lung cancers. Neither the ACS nor USPSTF have specific recommendations for prostate cancer screening. These cancers collectively account for only 42% of annual cancer incidence in people aged 50-79 years. It has been estimated that detection of cancer at an earlier stage could reduce cancer-related deaths by 15% or more within 5 years. Some of the available screening tests reduce cancer-specific mortality, but are associated with high false-positive rates, overdiagnosis, and overtreatment.

Galleri is a Multi-Cancer Early Detection (MCED) test developed for the early detection of multiple asymptomatic cancers that lack recommended screening tests, using a blood sample. DNA (cell free DNA) is shed into the blood stream both by tumor cells as well as healthy cells. The Galleri test uses Next Generation Sequencing (NGS) and machine-learning algorithms to isolate cell-free DNA and analyze more than 100,000 DNA regions and over a million specific DNA sites, to screen for a signal shared by cancers. The test looks for cell-free DNA and identifies whether it comes from healthy or cancer cells. DNA from cancer cells has specific methylation patterns that identify it as a cancer signal. Methylation patterns also contain information about the tissue type or organ associated with the cancer signal. So, once a cancer signal is detected, the Galleri test predicts the Cancer Signal Origin, or the tissue or organ where the cancer signal originated, to help guide diagnostic evaluation. The Galleri test is recommended for use in adults with an elevated risk for cancer, such as those aged 50 or older, and should be used in addition to routine cancer screening tests. Galleri is not recommended in individuals who are pregnant, 21 years old or younger, or undergoing active cancer treatment.

A validation study (Circulating Cell-free Genome Atlas study-CCGA) was conducted to evaluate the accuracy of the Galleri test. This study included 2,823 people with a known diagnosis of cancer and 1,254 healthy people. The overall Sensitivity for cancer signal detection was 51.5% and the Specificity was 99.5%. The sensitivity of the test increased with advanced cancer stages. Cancer signals were detected across over 50 cancer types and the overall accuracy of predicting Cancer Signal Origin in those who tested true positive was 88.7% (Ann Oncol. 2021;32:1167-1177).

PATHFINDER was a pilot, prospective cohort study conducted to investigate the feasibility of MCED testing for cancer screening. This study included 6,621 participants from oncology and primary care outpatient clinics at seven U.S. health networks who underwent MCED blood testing. Participants were 50 years or older, with no signs or symptoms of cancer, and majority were women (63.5%) and White (91.7%). Approximately 56% of participants had additional risk factors such as smoking, germline cancer predisposition, or personal history of treated cancer. The Primary outcome was time to diagnosis, and extent of diagnostic testing required to confirm the presence or absence of cancer.

MCED testing detected a cancer signal in 1.4% of the total patient sample of whom 38% had cancer confirmed (true positives), while 62% had no cancer (false positives). In patients in whom no cancer signal was detected, 95.5% were true negatives, 1.3% was false negatives, and 3.2% did not have cancer-status assessment at the end of the study. The tests accuracy in predicting the primary cancer location (Cancer Signal Origin) among the true positives was high at 97%. The median time to achieving a diagnostic resolution was 79 days, 57 days in true-positive patients and 162 days in false-positive ones. Fewer procedures were done in participants with false-positive results compared to true-positive results (30% versus 82% respectively) and few participants had surgery (one with a false-positive result and three with a true-positive result).

Among participants whose testing was true-positive and who had a confirmed new cancer diagnosis, nearly half (48%) were detected at an early stage (Stage I-II) when the potential for curative treatment is increased. Further, 74% of the MCED-detected cancers were cancer types that do not currently have USPSTF screening recommendations. These included cancers of the bile duct, pancreas, small intestine, and spindle cell neoplasm, which are all associated with high mortality rates and may be amenable to surgical resection at early stages.

In the 12 months study period, 121 cancers were diagnosed, of whom 29% had a cancer signal detected by MCED, while 31% were detected thru screening and 40% were detected clinically. The overall Positive Predictive Value of MCED was 38%, Negative Predictive Value was 98.6%, and specificity was 99.1%. The cancer yield rate was 0.53% (number needed to screen to find one MCED-detected cancer was 189).

The researchers concluded that this study demonstrates the feasibility of screening for multiple cancers using a blood test and lays the foundation for large, controlled trials necessary to establish clinical utility and cost-effectiveness. Multi Cancer Early Detection test was also able to accurately predict tumor origin, and the diagnosis of cancer was established in less than 2 months in the true-positive patients.

Blood-based tests for multicancer early detection (PATHFINDER): a prospective cohort study. Schrag D, Beer TM, McDonnell CH, et al. The Lancet 2023;402:1251-1260.

KEYTRUDA® in Combination with HER2 Blockade Improves PFS in Gastric and GE Junction Cancer

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SUMMARY: Gastroesophageal cancers consist of a group of heterogeneous tumors, including gastric cancer, gastroesophageal junction cancer, and esophageal cancer. The majority of gastric and gastroesophageal junction cancers are adenocarcinomas, while the two main histological subtypes of esophageal cancer are esophageal adenocarcinoma and esophageal squamous cell carcinoma. The American Cancer Society estimates that in the US about 26,500 new gastric cancer cases and 21,560 new esophageal cancers will be diagnosed in 2023 and about 11,130 and 16,120 people respectively, will die of the disease. It is one of the leading causes of cancer-related deaths in the world. Patients with localized disease (Stage II and Stage III) are often treated with multimodality therapy and 40% of the patients may survive for 5 years or more. However, majority of the patients with gastric and gastroesophageal junction adenocarcinoma have advanced disease at the time of initial presentation and have limited therapeutic options with little or no chance for cure.

The Human Epidermal growth factor Receptor (HER) or erbB family of receptors, consist of HER1, HER2, HER3 and HER4. Approximately 15-20% of advanced gastric and gastroesophageal (GE) junction cancers, overexpress or have amplification of the HER2 oncogene. These patients often receive first line treatment with a combination of chemotherapy plus anti-HER2 antibody, Trastuzumab, as there is Overall Survival (OS) benefit with this combination regimen. Pembrolizumab (KEYTRUDA®) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor expressed on activated T cells, and blocks its interaction with ligands PD-L1 and PD-L2. It thereby reverses the PD-1 pathway-mediated inhibition of the immune response and unleashes the tumor-specific effector T cells. In two Phase II studies, Pembrolizumab in combination with Trastuzumab and chemotherapy showed promising efficacy with manageable toxicities. The FDA in 2021 granted accelerated approval to Pembrolizumab in combination with Trastuzumab, Fluoropyrimidine and Platinum-containing chemotherapy for the first-line treatment of patients with locally advanced unresectable or metastatic HER2 positive gastric or gastroesophageal junction adenocarcinoma, based on Overall Response Rates (ORR).

KEYNOTE-811 is an ongoing, global, multicenter, randomized Phase III trial which evaluated the benefit of adding Pembrolizumab to Trastuzumab and chemotherapy in patients with locally advanced unresectable or metastatic HER2-positive gastric or gastroesophageal junction adenocarcinoma. In this study, 698 treatment naïve eligible patients (N=698) were randomly assigned 1:1 to receive Pembrolizumab 200 mg IV (N=350) or placebo (N=348) every 3 weeks plus Trastuzumab and investigator’s choice of Fluorouracil/Cisplatin or Capecitabine/Oxaliplatin. Trastuzumab was given at 6 mg/kg IV once every 3 weeks after a loading dose of 8 mg/kg IV. Chemotherapy consisted of 5-FU 800 mg/m2 IV on days 1 to 5 of each 3-week cycle and Cisplatin 80 mg/m2 IV once every 3 weeks, or Capecitabine 1,000 mg/m2 orally twice daily on days 1 to 14 of each 3-week cycle and Oxaliplatin 130 mg/m2 IV once every 3 weeks. Treatment was continued for up to 35 cycles or until disease progression or unacceptable toxicity. Approximately 81% were male and patients were stratified by PD-L1 status, and chemotherapy received. Over 80% of patients had a PD-L1 Combined Positive Score of 1 or more. The dual Primary end points of the trial were Progression Free Survival (PFS) and Overall Survival (OS). Secondary end points included Objective Response Rate (ORR), Duration of Response, and Safety. The researchers reported the results at the third interim analysis, after a median follow up of 38.5 months.

At the third interim analysis, the results continued to show superiority with the addition of Pembrolizumab to Trastuzumab and chemotherapy. The median PFS with Pembrolizumab versus placebo was 10 months versus 8.1 months, respectively (HR = 0.73; P=0.0002). This represented a 27% reduction in risk for progression with Pembrolizumab versus placebo. The median OS showed numerical improvement and was 20.0 months versus 16.8 months (HR=0.84), but did not meet prespecified criteria for significance. Follow up for Overall Survival is continuing, and results will be updated at the final analysis. Patients whose tumors had PD-L1 Combined Positive Score of 1 or more benefitted the most, and there was little to no benefit among patients whose tumors had PD-L1 Combined Positive Scores less than 1. The researchers had previously reported an ORR of 74% in the the Pembrolizumab group and 52% in the placebo group, yielding a 22% improvement for the Pembrolizumab group (P=0.00006). Disease Control Rates were 96.2% versus 89.3% respectively. Grade 3 or more treatment-related adverse events were higher among patients assigned to Pembrolizumab versus placebo group (58% versus 51%). The most common treatment-related adverse events of any grade were diarrhea, nausea and anemia.

The authors concluded that Pembrolizumab when combined with first line Trastuzumab and chemotherapy significantly improved Progression Free Survival when compared to placebo, in metastatic HER2-positive gastroesophageal cancer. This benefit was specifically noted among patients with tumors with a PD-L1 Combined Positive Score of 1 or more. Follow up for Overall Survival is ongoing and will be updated at the final analysis.

Pembrolizumab plus trastuzumab and chemotherapy for HER2-positive gastric or gastro-oesophageal junction adenocarcinoma: interim analyses from the phase 3 KEYNOTE-811 randomised placebo-controlled trial. Janjigian YY, Kawazoe A, Bai Y, et al. Published:October 20, 2023. DOI:https://doi.org/10.1016/S0140-6736(23)02033-0