Late Breaking Abstract – ASCO 2022: Panitumumab Combined with mFOLFOX6 Improves Overall Survival in Left-Sided RAS Wild-Type Metastatic Colorectal Cancer

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 151,030 new cases of CRC will be diagnosed in the United States in 2022 and about 52,580 patients are expected to die 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 include Oxaliplatin or Irinotecan, in combination with a Fluoropyrimidine and Leucovorin (FOLFOX or FOLFIRI), along with a VEGF targeting agent such as Bevacizumab or EGFR targeting agents such as Cetuximab and Panitumumab. However numerous studies have failed to clearly establish that any of these combination regimens would be superior for any given patient based on clinical factors. Nonetheless, majority of patients with metastatic colorectal cancer receive FOLFOX-based first line treatment in the US. 

A retrospective evaluation from the Phase III 80405 clinical trial which included data from 1,025 patients with KRAS wild-type disease, concluded that the biology of tumors originating in the right colon may be different from those originating in the left colon, with Cetuximab showing superiority over Bevacizumab, when combined with chemotherapy, in KRAS wild-type patients with left-sided colon cancer. (J Clin Oncol 34, 2016: suppl; abstr 3504).

Panitumumab (VECTIBIX®) is a human IgG2 kappa monoclonal antibody, that targets and antagonizes Epidermal Growth Factor Receptor (EGFR). The PARADIGM Trial is a multicenter, open-label, prospective, Phase III study conducted in Japan, to evaluate the efficacy and superiority of mFOLFOX6 plus Panitumumab compared to mFOLFOX6 plus Bevacizumab, in the first line treatment of chemotherapy-naïve patients with RAS wild type (KRAS/NRAS gene) metastatic colorectal cancer and left-sided primary tumors (descending colon, sigmoid colon, and rectum). In this first prospective randomized study, a total of 400 patients received Panitumumab and 402 received Bevacizumab. Both groups received mFOLFOX6. Most of the patients had left sided tumors (N=614) of whom 312 patients received Panitumumab with chemotherapy, whereas 292 patients received Bevacizumab with chemotherapy. The Primary endpoint of Overall Survival (OS) was hierarchically tested in patients with left-sided tumors, followed by evaluation in the entire study population. Key Secondary endpoints included Progression Free Survival (PFS), Objective Response Rate (ORR), and curative resection (R0) rate. Overall Survival in patients with left-sided tumors was analyzed after a median follow up of 61 months.

The study met its Primary endpoint and Panitumumab in combination with mFOLFOX6 significantly improved median Overall Survival, compared to Bevacizumab plus mFOLFOX6 in the left-sided tumor population, with a 18% lower risk of death (37.9 months versus 34.3 months; HR=0.82; P=0.031). When the data was subsequently analyzed for the entire study group, the OS benefit also significantly favored Panitumumab combination over Bevacizumab combination (median 36.2 months versus 31.3 months; HR=0.84; P=0.030). This difference however appears to be driven by the left-sided tumor population, as there was no significant OS improvement seen for patients with right-sided tumors in an exploratory analysis (median 20.2 months versus 23.2 months; HR=1.09).

There was no significant difference in the median PFS between treatment groups in the population with left-sided tumors and the median PFS was 13.7 months with Panitumumab combination and 13.2 months with Bevacizumab combination (HR=0.98). However, both Objective Response Rate and curative (R0) resection rate was higher in the Panitumumab group compared with Bevacizumab group, in the population with left-sided tumors. The Objective Response Rate was 80.2% versus 68.6%, the curative (R0) resection rate 18.3% versus 11.6% and the median duration of response was 13.1 versus 11.2 months respectively. Treatment with Panitumumab, resulted in more skin, mucosal and nail toxicities, commonly associated with EGFR inhibitors, and no new safety signal were observed.

It was concluded that in this first and largest randomized first line study comparing the efficacy of different targeted therapies in combination with standard doublet chemotherapy based on tumor sidedness, Panitumumab in combination with mFOLFOX6 significantly improved Overall Survival, resulted in a higher Objective Response Rate and a higher curative resection rate, in patients with RAS wild-type and left-sided metastatic colorectal cancer, compared with patients who received Bevacizumab plus mFOLFOX6. These findings emphasize the importance of comprehensive biomarker testing, as well as taking into consideration tumor location, in patients with metastatic colorectal cancer.

Panitumumab (PAN) plus mFOLFOX6 versus bevacizumab (BEV) plus mFOLFOX6 as first-line treatment in patients with RAS wild-type (WT) metastatic colorectal cancer (mCRC): Results from the phase 3 PARADIGM trial. Yoshino T, Watanabe J, Shitara K, et al. DOI:10.1200/JCO.2022.40.17_suppl.LBA1 Journal of Clinical Oncology 40, no. 17_suppl (June 10, 2022) LBA1.

Late Breaking Abstract – ASCO 2022: Survival Benefit with TRODELVY® in Hormone Receptor Positive/HER2-Negative Metastatic Breast Cancer

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. Approximately 290,560 new cases of breast cancer will be diagnosed in 2022 and about 43,780 individuals will die of the disease, largely due to metastatic recurrence. Approximately 70% of breast tumors in patients with metastatic disease are Estrogen Receptor (ER) and/or Progesterone Receptor (PR) positive and HER2-negative. These patients are often treated with single agent endocrine therapy, endocrine therapy in combination with CDK4/6 inhibitor, or single agent chemotherapy. Resistance to hormonal therapy occurs in a majority of the patients and there is therefore an unmet need for agents with novel mechanisms of action.

TRODELVY® (Sacituzumab govitecan) is an Antibody-Drug Conjugate (ADC) in which SN-38, an active metabolite of Irinotecan, a Topoisomerase I inhibitor, is coupled to the humanized Anti-Trophoblast cell-surface antigen 2 (Trop-2) monoclonal antibody (hRS7 IgG1κ), through the cleavable CL2A linker. SN-38 cannot be given directly to patients because of its toxicity and poor solubility. Trop-2, a transmembrane calcium signal transducer, stimulates cancer-cell growth, and this cell surface receptor is overexpressed in several epithelial cancers including cancers of the breast, colon and lung, and has limited expression in normal human tissues. Trop-2 is expressed in more than 85% of breast tumors including Triple Negative Breast Cancer. Upon binding to Trop-2, the anti-TROP-2 monoclonal antibody is internalized and delivers SN-38 directly into the tumor cell, making it a suitable transporter for the delivery of cytotoxic drugs. Further, the cleavable linker enables SN-38 to be released both intracellularly into the tumor cells, as well as the tumor microenvironment, thereby allowing for the delivery of therapeutic concentrations of the active drug in bystander cells to which the conjugate has not bound. Thus, TRODELVY®-bound tumor cells are killed by intracellular uptake of SN-38, whereas the adjacent tumor cells are killed by the extracellular release of SN-38.

TRODELVY® was approved by the FDA in 2021 for patients with unresectable, locally advanced or metastatic Triple Negative Breast Cancer, who have received two or more prior systemic therapies, at least one of them for metastatic disease. In the IMMU-132 Phase I/II study, the Hormone Receptor positive (HR+)/HER2-negative cohort of patients with metastatic breast cancer patients had an Objective Response Rate (ORR) of 31.5%, median Progression Free Survival (PFS) of 5.5 months and median Overall Survival (OS) of 12 months, with manageable toxicities, when treated with TRODELVY®.

TROPiCS-02 is a global, open-label, randomized, Phase III study, conducted to confirm the benefit of TRODELVY® in HR+/HER2- negative advanced breast cancer. In this study, 543 patients with HR+/HER2-negative, unresectable, locally advanced or metastatic breast cancer, were randomly assigned 1:1 to receive TRODELVY® 10 mg/kg IV on D1 and 8, every 21 days (N=272), or treatment of physician’s choice, which included single agent treatment with either Capecitabine, Eribulin, Vinorelbine, or Gemcitabine (N=271). Treatment was continued until disease progression or unacceptable toxicity. Both treatment groups were well balanced. Eligible patients had 3 median prior chemotherapy regimens for metastatic breast cancer, and one prior therapy for metastatic breast cancer was allowed if disease progressed in 12 months or less after neoadjuvant chemotherapy. Patients were required to have received endocrine therapy, a CDK4/6 inhibitor and at least one prior therapy with a Taxane in any setting. Majority of patients had visceral metastases (95%), 86% had prior endocrine therapy for metastatic breast cancer for at least 6 months, and 60% and 38% received prior CDK4/6 inhibitors for 12 months or less, and for more than 12 months, respectively. The Primary endpoint was Progression Free Survival (PFS) by blinded Independent Central Review (final analysis) and key Secondary endpoint was Overall Survival (OS) at the first planned interim analysis.

The median Progression Free Survival was 5.5 months with TRODELVY® versus 4 months with standard chemotherapy (HR=0.66; P=0.0003), representing a 34% improvement in PFS with TRODELVY®. This benefit was seen across all treatment subgroups including those who were 65 years or older, those who were heavily pretreated, as well as those with visceral metastases. The Objective Response Rate (ORR) was 21% with TRODELVY® versus 14% with standard chemotherapy. The Clinical Benefit Rate was also higher with TRODELVY® versus standard chemotherapy (34% versus 22%) and median duration of response was 7.4 months and 5.6 months respectively. Overall Survival data were immature, but there was a numerical, non-significant improvement in the median Overall Survival noted in the TRODELVY® group, compared to the standard chemotherapy group (13.9 months versus 12.3 months; HR=0.84; P=0.14), respectively. Treatment with TRODELVY® also resulted in an overall health-related Quality of Life benefit over chemotherapy, with delayed deterioration in fatigue and global health status/ Quality of Life scales, according to the researchers. Grade 3 or more adverse events were observed in 74% of patients receiving TRODELVY® and in 60% of those receiving chemotherapy, and the most common toxicities associated with TRODELVY® were diarrhea and neutropenia.

It was concluded from this landmark analysis that treatment with TRODELVY® resulted in a statistically significant and clinically meaningful improvement in Progression Free Survival, compared to standard chemotherapy, in heavily pre-treated patients with HR+/HER2-negative, endocrine-resistant, unresectable, locally advanced or metastatic breast cancer, and should therefore be considered as a new treatment option for this patient population.

Primary results from TROPiCS-02: A randomized phase 3 study of sacituzumab govitecan (SG) versus treatment of physician’s choice (TPC) in patients (Pts) with hormone receptor–positive/HER2-negative (HR+/HER2-) advanced breast cancer. Rugo HS, Bardia A, Marmé F, et al. J Clin Oncol 40, 2022 (suppl 17; abstr LBA1001)

Late Breaking Abstract – ASCO 2022: Adagrasib in KRAS G12C Mutated Non Small Cell Lung Cancer

SUMMARY: The American Cancer Society estimates that for 2022, about 236,740 new cases of lung cancer will be diagnosed and 135,360 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.

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. The KRAS protein is a GTPase, and converts GTP into GDP. To transmit signals, the KRAS protein must be turned on by binding to a molecule of GTP. When GTP is converted to GDP, the KRAS protein is turned off or inactivated, and when the KRAS protein is bound to GDP, it does not relay signals to the cell nucleus. The 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 25% of Non Small Cell Lung Cancers (NSCLC) and in 3-5% of colorectal cancers and other solid cancers. KRAS G12C is one of the most prevalent driver mutations in NSCLC and accounts for a greater number of patients than those with ALK, ROS1, RET, and TRK 1/2/3 mutations combined. KRAS G12C cancers are genomically more heterogeneous and occur more frequently in current or former smokers, and are likely to be more complex genomically than EGFR mutant or ALK rearranged cancers. G12C is a single point mutation with a Glycine-to-Cysteine substitution at codon 12. This substitution favors the activated state of KRAS, resulting in a predominantly GTP-bound KRAS oncoprotein, amplifying signaling pathways that lead to oncogenesis.

Adagrasib is a potent, orally available, small molecule covalent inhibitor of KRAS G12C. This drug irreversibly and selectively binds KRAS G12C in its inactive, GDP-bound state. Unlike LUMAKRAS® (Sotorasib), which is also a selective covalent inhibitor of KRAS G12C, Adagrasib has a longer drug half-life of 23 hours, as compared to 5 hours for LUMAKRAS®, has dose-dependent extended exposure, and can penetrate the CNS. Approximately, 27-42% of patients with NSCLC harboring KRAS G12C mutations have CNS metastases, with poor outcomes.

KRYSTAL-1 is a Phase I/II multiple expansion cohort trial involving patients with advanced solid tumors harboring a KRAS G12C mutation. Adagrasib demonstrated clinical activity in patients with KRAS G12C-mutated solid tumors, including colorectal, pancreatic, and biliary tract cancers. Further, preliminary data from two patients with untreated CNS metastases from a Phase 1b cohort showed antitumor activity against CNS metastases, with satisfactory concentrations of Adagrasib in the CSF.

The researchers in this publication reported the results from Cohort A, a Phase 2 cohort of the KRYSTAL-1 study in which Adagrasib at a dose of 600 mg orally twice daily was evaluated in patients with KRAS G12C-mutated NSCLC, previously treated with chemotherapy and anti-Programmed Death 1 (PD-1) or Programmed Death Ligand 1 (PD-L1) therapy. This registration study included a total of 116 unresectable or metastatic NSCLC patients, with histologically confirmed diagnosis, with KRAS G12C mutation (detected in tumor tissue at a local or central laboratory), who had previously received treatment with at least one platinum-containing chemotherapy regimen and checkpoint inhibitor therapy (in sequence or concurrently), and who had measurable tumor lesions. Enrolled patients received Adagrasib 600 mg capsule twice daily, and treatment was continued until disease progression or unacceptable toxicities. The median patient age was 64 years, 97% had adenocarcinoma histology, 98% had both platinum based therapy and checkpoint inhibitor therapy, and 21% of patients had CNS metastases. Key exclusion criteria included active CNS metastases (patients were eligible if CNS metastases were adequately treated and neurologically stable), carcinomatous meningitis, and previous treatment with a KRAS G12C inhibitor. Exploratory Biomarker Analyses included candidate biomarkers (PD-L1 Tumor Proportion Score and mutational status of STK11, KEAP1, TP53, and CDKN2A on tumor-tissue specimens, blood specimens, or both, for their association with tumor response. The Primary end point was Objective Response Rate as assessed by blinded Independent Central Review. Secondary end points included the Duration of Response, Progression Free Survival, Overall Survival, and safety.

The median follow up was 12.9 months and the median duration of treatment was 5.7 months. The confirmed Objective Response Rate was 42.9% and the median Duration of Response was 8.5 months. The median Progression Free Survival was 6.5 months and the median Overall Survival was 12.6 months, at a median follow up of 15.6 months. Among 33 patients with previously treated, stable CNS metastases, the intracranial confirmed Objective Response Rate was 33.3%. Treatment-related adverse events occurred in 97.4% of the patients and 53% were Grade 1 or 2 toxicities. Adagrasib was discontinued in 6.9% of patients due to adverse events.

It was concluded that among patients with previously treated KRAS G12C-mutated NSCLC, Adagrasib showed significant clinical efficacy without new safety signals, and encouraging intracranial activity. The researchers added that these are the first clinical data demonstrating CNS-specific activity of a KRAS G12C inhibitor in this patient population.

Adagrasib in Non–Small-Cell Lung Cancer Harboring a KRASG12C Mutation. Jänne PA, Riely GJ, Gadgeel SM, et al. DOI: 10.1056/NEJMoa2204619

Late Breaking Abstract – ASCO 2022: Adjuvant Radiotherapy May Be Omitted in Select Patients with Luminal A Breast Cancer

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. Approximately 290,560 new cases of breast cancer will be diagnosed in 2022 and about 43,780 individuals will die of the disease, largely due to metastatic recurrence.

Patient undergoing breast conserving surgery, often receive adjuvant breast radiation therapy to reduce the risk of local recurrence. Radiation therapy however is inconvenient, expensive and is associated with acute and late toxicities. Previously published study by Kunkler IH, et al. (Lancet Oncol. 2015;16:266-273) concluded that radiotherapy could be avoided in a subset of elderly patients with low risk breast cancer following breast conserving surgery.

Molecular-Subtypes-of-Breast-CancerConventional clinical pathological factors have limited ability to identify breast cancer patients with low risk disease, who could avoid radiation therapy. Molecular defined intrinsic subtypes of breast cancer can provide additional prognostic information. Breast cancer is heterogeneous malignancy and using global gene expression analyses, 5 breast cancer intrinsic subtypes have been established. They include Luminal A, Luminal B, HER2-enriched, Basal-like, and Normal breast-like group. Luminal A breast cancer patients have the lowest risk of recurrence. In a retrospective analysis of women over age 60 years, with Luminal A, Grade 1-2, T1N0 breast cancer, treated with breast conserving surgery and endocrine therapy alone, the local recurrence rate was low (JCO 2015; 33:2035). However, the utility of combining molecular subtype (Luminal A subtype) with clinical pathological factors, to guide radiotherapy decision-making, has not been prospectively evaluated.

LUMINA is a prospective multicenter single-arm, cohort study, in which 501 women, 55 years and older, who had undergone breast conserving surgery for breast cancer, were enrolled. Eligible patients had invasive ductal T1N0, Grade 1-2, Luminal A breast cancer, had undergone breast conserving surgery, with excision margins of at least 1 mm and sentinel lymph node biopsy, omitted radiotherapy, and had received adjuvant endocrine therapy for at least 5 years. Luminal A subtype was defined as ER 1% or more, PR more than 20%, HER2 negative and Ki67 13.25% or less. Ki67 immunohistochemistry was performed centrally in one of three Canadian laboratories using International Ki67 Working Group methods. The median patient age was 67 years, 66% had Grade 1 tumors, 88% of patients were less than 75 years, and the median tumor size was 1.1 cm. Patients were followed every six months for the first two years and then yearly. The Primary outcome was local recurrence defined as time from enrollment to any invasive or non-invasive cancer in the ipsilateral breast. Secondary endpoints included contralateral breast cancer, Relapse Free Survival (RFS) based on any recurrence, Disease Free Survival, and Overall Survival.

At a median follow up of 5 years, the local recurrence rate was 2.3% and the rate of contralateral breast cancer was 1.9%. The 5-year Relapse Free Survival, Disease Free Survival and Survival rate was 97.3%, 89.9% and 97.2% respectively.

The authors concluded that among women 55 years of age and over, with low grade Luminal A breast cancer, omission of radiation therapy following breast conserving surgery and treatment with endocrine therapy alone for 5 years or more, resulted in very low rates of local recurrence at 5 years. The researchers added that approximately 30,000-40,000 women per year in North America, predominantly in the US, could avoid the morbidity, expense, and inconvenience of radiotherapy.

LUMINA: A prospective trial omitting radiotherapy (RT) following breast conserving surgery (BCS) in T1N0 luminal A breast cancer (BC). Whelan TJ, Smith S, Nielsen TO, et al. J Clin Oncol. 2022;40(suppl 17):LBA501. doi:10.1200/JCO.2022.40.17_suppl.LBA501

Late Breaking Abstract – ASCO 2022: Circulating Tumor DNA in the Peripheral Blood Can Guide Adjuvant Therapy Decision in Stage II Colon Cancer

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 151,030 new cases of CRC will be diagnosed in the United States in 2022 and about 52,580 patients are expected to die of the disease. The lifetime risk of developing CRC is about 1 in 23.

Adjuvant chemotherapy for patients with resected, locally advanced, node-positive (Stage III) colon cancer has been the standard of care since the 1990s. Even though 80% of patients with Stage II colon cancer are cured with surgery alone, adjuvant chemotherapy is recommended for patients who have Stage II colon cancer with high-risk clinicopathological features, including tumor penetration of the serosa (T4 disease). However, the benefit of adjuvant chemotherapy for patients with Stage II disease remains unclear, with less than 5% of patients benefitting from adjuvant chemotherapy. There is therefore an unmet need for more precise markers to predict risk of recurrence after surgery for Stage II colon cancer, other than clinicopathological risk factors, and thus avoid exposure to unnecessary chemotherapy.

Circulating Tumor DNA (ctDNA) refers to DNA molecules that circulate in the bloodstream after cell apoptosis or necrosis, and can be detected in the cell-free component of peripheral blood samples (Liquid Biopsy) in almost all patients with advanced solid tumors including advanced colorectal cancer. ctDNA is a valuable biomarker and is directly evaluated for evidence of Minimal Residual Disease and allows early detection of relapse. Several studies have shown that detectable ctDNA following curative intent surgery for early stage cancers, including those with Stage II colon cancer, is associated with a very high risk of recurrence (more than 80%) without further adjuvant therapy. It has remained unclear whether adjuvant treatment is beneficial for these ctDNA-positive patients who are at high risk for recurrence.

The Circulating Tumor DNA Analysis Informing Adjuvant Chemotherapy in Stage II Colon Cancer (DYNAMIC) trial is a randomized trial designed to investigate whether a ctDNA-guided treatment approach could reduce the use of adjuvant treatment without compromising the risk of recurrence, as compared with a standard approach in patients with Stage II colon cancer.
The researchers also evaluated outcomes among ctDNA-positive patients who received adjuvant chemotherapy, to assess the benefit of treating this high-risk group of patients, as well as outcomes among ctDNA-negative patients whose disease was managed by surveillance alone. In this Phase II, multicenter, randomized, controlled trial of biomarker-driven adjuvant therapy, 455 patients with resected, histologically confirmed, Stage II (T3 or T4, N0, M0) colon or rectal adenocarcinoma with negative resection margins, were randomly assigned in a 2:1 ratio to have their disease managed according to ctDNA results-ctDNA-guided management group (N=302) or managed by the treating clinician according to standard clinicopathological criteria-standard management group (N=153). Plasma specimens were obtained for ctDNA analysis from all patients at week 4 and week 7 after surgery. For patients assigned to ctDNA-guided management, week 4 and week 7 specimens were analyzed concurrently, and ctDNA results were made available to the treating clinician 8 to 10 weeks after surgery. Patients with a positive ctDNA result at either week 4 or week 7 received adjuvant single-agent fluoropyrimidine or Oxaliplatin-based chemotherapy, with the treatment regimen chosen at the treating physician’s discretion. Patients with negative ctDNA results at both week 4 and week 7 were not treated with adjuvant chemotherapy. In the standard management group, all treatment decisions were based on conventional clinicopathological criteria. This trial used a ctDNA assay specifically designed for detection of Minimal Residual Disease with very high sensitivity (a variant allele frequency limit of detection as low as 0.01%), as well as serial blood samples for ctDNA analysis to decrease the risk of a false negative result. In this study, ctDNA probes were personalized on the basis of specific mutations identified in tumor tissue.

Enrolled patients had an ECOG PS of 0-2 and had to be medically eligible to receive adjuvant Oxaliplatin-based or single-agent fluoropyrimidine chemotherapy. Patients were stratified according to tumor stage (T3 or T4) and patients with evidence of macroscopic metastatic disease on CT of the chest, abdomen, and pelvis performed within 8 weeks before enrollment, presence of synchronous primary colorectal cancer, or treatment with neoadjuvant chemoradiotherapy, were excluded. Patients were enrolled within 3 weeks following surgery, and an adequate resected tumor specimen had to be provided for mutation analysis by 4 weeks after surgery. The treatment groups were well balanced, the median age of the patients was 64 years, 85% of patients had T3 disease, 15% had T4 disease, and 5% had a lymph node yield of less than 12. Clinical high risk disease was defined as one or more of the following clinicopathological risk features: T4 lesion, poor tumor differentiation, lymph node yield less than 12, lymphovascular invasion, tumor perforation, or bowel obstruction, in association with a proficient mismatch-repair tumor, which was present in 40% of patients. The Primary efficacy end point was noninferiority of ctDNA-guided management to standard management with regards to 2-year Recurrence Free Survival (RFS). A key Secondary end point was to determine whether fewer patients would receive adjuvant chemotherapy with the ctDNA-guided approach.

At a median follow up of 37 months, the 2-year RFS was 93.5% with ctDNA-guided management and 92.4% with standard management, meeting the noninferiority criterion. Further, a lower percentage of patients in the ctDNA-guided group received adjuvant chemotherapy than in the standard-management group (15% versus 28%).

The authors concluded that a ctDNA-guided approach to the treatment of Stage II colon cancer reduced adjuvant chemotherapy use without compromising Recurrence Free Survival. Studies are underway assessing the role of escalated chemotherapy in ctDNA-positive patients and deescalation of chemotherapy in ctDNA-negative patients with Stage II colorectal cancer.

Circulating Tumor DNA Analysis Guiding Adjuvant Therapy in Stage II Colon Cancer. Tie J, Cohen JD, Lahouel K, et al. for the DYNAMIC Investigators. N Engl J Med 2022; 386:2261-2272

Late Breaking Abstract – ASCO 2022: IMBRUVICA® plus Bendamustine and Rituximab for Older Patients with Untreated Mantle Cell Lymphoma

SUMMARY: The American Cancer Society estimates that in 2022, about 80,470 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,250 individuals will die of this disease. In the US, approximately 3,300 new cases of MCL are diagnosed each year. Mantle Cell Lymphoma is an aggressive B-cell lymphoma and accounts for approximately 6% of all Non Hodgkin Lymphomas in adults, and is associated with a high relapse rate following dose-intensive therapies. Early and late relapses in patients with MCL have been attributed to persistence of residual disease.

Majority of patients with MCL are elderly and are not candidates for aggressive treatment or Autologous Stem Cell Transplantation. These patients often receive less aggressive first line therapy such as Bendamustine plus Rituximab, and this regimen has demonstrated superior Progression Free Survival compared to R-CHOP, with a better safety profile. Further, the addition of Rituximab maintenance therapy after induction therapy with Bendamustine and Rituximab has shown significantly prolonged Progression Free Survival or Overall Survival in two independent observational studies.

Bruton’s Tyrosine Kinase (BTK) is a member of the Tec family of kinases, downstream of the B-cell receptor and is predominantly expressed in B-cells. It is a mediator of B-cell receptor signaling in normal and transformed B-cells. Following binding of antigen to the B-Cell Receptor, kinases such as Syk (Spleen Tyrosine Kinase), Lyn (member of the Src family of protein tyrosine kinases) and BTK (Bruton’s Tyrosine Kinase) are activated, with subsequent propagation through PI3K/Akt, MAPK, and NF-κB pathways. This results in B-cell activation and proliferation. The 3 BTK inhibitors presently approved by the FDA for MCL include, IMBRUVICA® (Ibrutinib) approved in 2013, CALQUENCE® (Acalabrutinib) approved in 2017, and BRUKINSA® (Zanubrutinib) approved in 2019.

Single agent IMBRUVICA® is presently approved by the FDA for the treatment of MCL patients who have received at least one prior therapy. In a Phase Ib study, the addition of IMBRUVICA® to Bendamustine and Rituximab therapy was safe and effective with a Complete Response Rate of 76%, among patients with untreated, relapsed, or refractory MCL.

SHINE study is an international, randomized, double-blind, Phase III trial , in which a combination of IMBRUVICA® with Bendamustine plus Rituximab and Rituximab maintenance therapy was compared with placebo with Bendamustine plus Rrituximab and Rituximab maintenance therapy, in elderly patients with untreated Mantle Cell Lymphoma (MCL). A total of 523 previously untreated patients, 65 years of age or older, who had a centrally confirmed diagnosis of Mantle Cell Lymphoma with Cyclin D1 overexpression or translocation breakpoints at t(11;14) were randomly assigned in a 1:1 ratio to receive either to six cycles of IMBRUVICA® along with Bendamustine and Rituximab (N=261) or six cycles of placebo along with Bendamustine and Rituximab (N=262). IMBRUVICA® 560 mg or placebo was administered orally once daily. Bendamustine was administered at 90 mg/m2 IV on days 1 and 2 of each 28 day cycle along with Rituximab 375 mg/m2 IV on day 1 of each 28 day cycle. Patients in either arm who achieved a Complete or Partial Response continued to receive IMBRUVICA® or placebo daily along with Rituximab maintenance therapy at a dose of 375 mg/m2 IV every 8 weeks for up to 12 additional doses. Patients with stable disease after induction treatment could continue to receive IMBRUVICA® or placebo until disease progression or unacceptable toxicities. Both treatment groups were well balanced. The median age of the patients was 71 years and eligible patients had documented Stage II to IV disease with at least one measurable site of disease that was at least 1.5 cm in the longest diameter. Patients were excluded if stem-cell transplantation was planned or if they had known CNS involvement. The Primary endpoint was Progression Free Survival (PFS). Secondary endpoints included Objective Response Rate, Complete Response Rate, Overall Survival and Safety.

The study met its Primary endpoint and at a median follow up of 84.7 months, the median PFS was 80.6 months in the IMBRUVICA® group and 52.9 months in the placebo group (HR for disease progression or death=0.75; P=0.01). The Complete Response Rate was 65.5% in the IMBRUVICA® group and 57.6% in the placebo group (P=0.06). The Overall Survival was similar in the two treatment groups. Grade 3 or 4 adverse events during treatment were 81.5% in the IMBRUVICA® group and 77.3% in the placebo group and the most common Grade 3 and 4 adverse events were rash, pneumonia, and atrial fibrillation.

The authors concluded that treatment with IMBRUVICA® in combination with standard chemoimmunotherapy significantly prolonged Progression Free Survival, and may be a new treatment option for elderly patients with newly diagnosed Mantle Cell Lymphoma, who may not be candidates for intensive chemotherapy or Autologous Stem Cell Transplantation.

Ibrutinib plus Bendamustine and Rituximab in Untreated Mantle-Cell Lymphoma. Wang ML, Jurczak W, Jerkeman M, et al. June 3, 2022. DOI: 10.1056/NEJMoa2201817.
DOI: 10.1200/JCO.2022.40.17_suppl.LBA7502 Journal of Clinical Oncology 40, no. 17_suppl (June 10, 2022) 

Overall Survival at 2 Years with LUMAKRAS® for KRAS G12C Positive Non Small Cell Lung Cancer

SUMMARY: The American Cancer Society estimates that for 2022, about 236,740 new cases of lung cancer will be diagnosed and 135,360 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.

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. The KRAS protein is a GTPase, and converts GTP into GDP. To transmit signals, the KRAS protein must be turned on, by binding to a molecule of GTP. When GTP is converted to GDP, the KRAS protein is turned off or inactivated, and when the KRAS protein is bound to GDP, it does not relay signals to the cell nucleus. The 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. KRAS G12C is one of the most prevalent driver mutations in NSCLC and accounts for a greater number of patients than those with ALK, ROS1, RET, and TRK 1/2/3 mutations combined. KRAS G12C cancers are genomically more heterogeneous and occur more frequently in current or former smokers, and are likely to be more complex genomically than EGFR mutant or ALK rearranged cancers. G12C is a single point mutation with a Glycine-to-Cysteine substitution at codon 12. This substitution favors the activated state of KRAS, resulting in a predominantly GTP-bound KRAS oncoprotein, amplifying signaling pathways that lead to oncogenesis.Inhibiting-KRAS-G12C

LUMAKRAS® (Sotorasib) is a first-in-class small molecule that specifically and irreversibly inhibits KRAS-G12C and traps KRAS-G12C in the inactive GDP-bound state. Preclinical studies in animal models showed that LUMAKRAS® inhibited nearly all detectable phosphorylation of Extracellular signal-Regulated Kinase (ERK), a key downstream effector of KRAS, leading to durable complete regression of KRAS-G12C tumors. The CodeBreaK clinical development program for LUMAKRAS® was designed to treat patients with an advanced solid tumor with the KRAS G12C mutation and address the longstanding unmet medical need for these cancers. This program has enrolled more than 800 patients across 13 tumor types since its inception.

CodeBreaK 100 is a Phase I and II, first-in-human, open-label, single arm, multicenter study, which enrolled patients with KRAS G12C-mutant solid tumors. Eligible patients must have received a prior line of systemic anticancer therapy, for their tumor type and stage of disease. The Phase II trial enrolled 126 patients with NSCLC, who had locally advanced or metastatic NSCLC with a KRAS G12C mutation, and had progressed on an immune checkpoint inhibitor and/or platinum-based chemotherapy. Patients with active brain metastases were excluded. Patient received LUMAKRAS® 960 mg orally once daily, until disease progression or unacceptable toxicity. The median age was 64 years, 52% were male, over 90% of patients had a smoking history, median number of prior lines of therapy was two, 92% had prior platinum-based chemotherapy and 90% had prior anti–PD-L1 therapy, 83% had both prior platinum-based chemotherapy and immunotherapy. The Primary end point of the trial was Overall Response Rate (ORR) as assessed by blinded Independent Central Review. Secondary end points included Duration of Response (DOR), Disease Control Rate (DCR), time to recovery, Progression Free Survival (PFS), Overall Survival (OS), and Safety. The examination of biomarkers served as an exploratory end point.

At the time of Primary analysis, at a median follow up of 12.2 months, the ORR was 37.1% and the median Duration of Response was 10 months. Based on the data from the primary analysis, the FDA in 2021 granted accelerated approval to LUMAKRAS®, for the treatment of patients with locally advanced or metastatic NSCLC, whose tumors harbor the KRAS G12C mutation, and who have received prior therapies.

For this updated analysis, the median follow up time for OS was 24.9 months, and the researchers included 174 patients enrolled in Phase I (N=48) and Phase II (N=126) portions of the CodeBreaK 100 trial, who were treated with LUMAKRAS®. The Overall Response Rate was 40.7% and the Disease Control Rate (DCR) was 83.7%. The median time to response was 6 weeks, the median Duration of Response was 12.3 month and 50.6% of responders remained in response for 12 months or more. The median PFS was 6.3 months and the median OS showed no change in the updated analysis, and was 12.5 months. At 1-year, the OS rate was 50.8% and the 2-year Overall Survival was 32.5%. The researchers performed additional analyses on both tumor and blood samples to identify biomarker profiles associated with durable clinical benefit and these showed that prolonged clinical benefit was observed regardless of Tumor Mutation Burden, PDL1 expression, and STK11 co-mutation status. Grade 3 or 4 treatment-related Adverse Events occurred in 21% of patients. Most adverse events were Grade 1 or 2, and treatment-related adverse events occurring in more than 10% of patients included diarrhea, elevated liver enzymes, nausea and fatigue.

It was concluded from this updated analysis that this is the longest follow up of patients on any KRAS G12C inhibitor, and LUMAKRAS® demonstrated meaningful and durable efficacy in patients with KRAS mutated NSCLC for whom treatment options are limited, following progression on first line treatment, and historically have had poor outcomes. Patients on LUMAKRAS® benefitted regardless of Tumor Mutation Burden, PDL1 expression, and STK11 co-mutation status. A global Phase III study (CodeBreaK 200) is underway, comparing LUMAKRAS® to Docetaxel in patients with KRAS G12C-mutated NSCLC.

Long-term outcomes with sotorasib in pretreated KRASp.G12C-mutated NSCLC: 2-year analysis of CodeBreaK100. Dy GK, Govindan R, Velcheti V, et al. Presented at: 2022 AACR Annual Meeting; April 8-13, 2022, New Orleans, LA. Abstract CT008.

Genetically Adjusted PSA Values May Improve the Accuracy of Prostate Cancer Detection

SUMMARY: Prostate cancer is the most common cancer in American men with the exclusion of skin cancer, and 1 in 9 men will be diagnosed with prostate cancer during their lifetime. It is estimated that in the United States, about 268,490 new cases of prostate cancer will be diagnosed in 2022 and 34,500 men will die of the disease.

PSA is one of the most widely used prostate cancer biomarkers, and the widespread use of PSA testing in the recent years has resulted in a dramatic increase in the diagnosis and treatment of prostate cancer. The management of clinically localized prostate cancer that is detected based on Prostate Specific Antigen (PSA) levels remains controversial and management strategies for these patients have included Surgery, Radiotherapy or Active Monitoring. However, it has been proposed that given the indolent nature of prostate cancer in general, majority of the patients do not benefit from treatment intervention and many patients die of competing causes. Further, treatment intervention can result in adverse effects on sexual, urinary, or bowel function. The U.S. Preventive Services Task Force (USPSTF) has recommended that population screening for prostate cancer with PSA should not be adopted as a public health policy, because the risks appeared to outweigh benefits, from detecting and treating PSA-detected prostate cancer. PSA elevation can be associated with several non-malignant conditions such as older age, infection, inflammation and Benign Prostatic Hypertrophy.

The researchers in this study hypothesized that the accuracy of PSA screening for prostate cancer could be improved by accounting for genetic factors that cause changes in PSA levels not associated with prostate cancer. The aim of this study was to characterize genetic determinants of PSA levels in cancer-free men, in order to personalize prostate cancer screening.

The researchers conducted a large Genome Wide Association Study of PSA, to improve Prostate cancer screening, by accounting for genetic factors that cause noncancer-related variations in PSA levels, thereby personalizing prostate cancer screening. This study involved 95,768 men without a diagnosis prostate cancer from the US, UK and Sweden. The researchers identified 128 PSA-related variants across the genome, including 82 novel variants that were not previously recognized, and created a polygenic score for PSA levels. This polygenic score provided a cumulative measure of each individual’s genetic predisposition to high PSA levels.

The authors validated the polygenic score by applying the score to PSA values of 5,725 individuals enrolled in the Prostate Cancer Prevention Trial (PCPT) and the 25,917 individuals enrolled in the Selenium and Vitamin E Cancer Prevention Trial (SELECT). The analysis showed that the score explained 7.3% of variation in baseline PSA values in PCPT trial and 8.8% of variation in baseline PSA values in the SELECT cohort, and the polygenic score was not associated with prostate cancer in both the prevention trials, confirming that the score reflected benign PSA variation.

The researchers next tested the ability of the polygenic score’s ability to improve detection of clinically significant prostate cancer and reduce over diagnosis among a real-world cohort at Kaiser Permanente. They adjusted each individual’s PSA values based on his unique polygenic score and estimated the impact of this adjustment on the PSA thresholds that trigger biopsy referrals. The authors estimated that by substituting the patient’s polygenic score for measured PSA values, 19.6% of negative biopsies in men without prostate cancer potentially could have been avoided, and 15.7% of biopsies could have been avoided in men who had indolent, low-grade prostate cancer (Gleason score <7), which represented 71% of all men.

The researchers then evaluated whether genetically adjusted polygenic score would better detect aggressive prostate cancer (Gleason score 7, PSA 10 ng/mL, T3-T4 stage and/or distant nodal metastases). It was noted that in both the PCPT and the SELECT cohorts, polygenic score was more strongly associated with aggressive prostate cancer than measured unadjusted PSA values. The polygenic score also exceeded the performance of the 269-variant genetic risk score.

The authors from this study concluded that genetically adjusted PSA (polygenic score) could reduce unnecessary testing and overdiagnosis of low-risk prostate cancer, and increase detection of aggressive tumors and thus make PSA a more useful and accurate screening biomarker. The researchers pointed out that the population studied, were primarily European descent, and the polygenic score will need to be validated in more diverse populations.

Genetic determinants of PSA levels improve prostate cancer screening. Kachuri L, Graff RE, Berndt SI, et al. Presented at: AACR Annual Meeting 2022; April 8-13; New Orleans, Louisiana. Abstract 1441/8.

PET Response-Based Radiotherapy De-Escalation in p16 Positive Oropharyngeal Cancer

SUMMARY: The American Cancer Society estimates that about 54,000 new cases of oral cavity or Oropharyngeal Cancer will be diagnosed in the US in 2022 and about 11,230 patients will die of the disease. According to the CDC, based on data from 2014 to 2018, about 46,143 HPV-associated cancers occur in the United States each year (25,719 among women, and 20,424 among men). Cervical cancer is the most common HPV-associated cancer among women, and Oropharyngeal cancers are the most common among men. There has been a significant increase in the incidence during the past several decades, due to changes in sexual practices.

HPV-positive Oropharyngeal Squamous Cell Carcinoma (OPSCC) is an entirely distinct disease entity from HPV-negative Oropharyngeal Squamous Cell Carcinoma. Patients with HPV-positive OPSCC tend to be younger males, who are former smokers or nonsmokers, with risk factors for exposure to High Risk HPV (HR-HPV). The HPV-positive primary Squamous Cell Carcinoma tend to be smaller in size, with early nodal metastases, and these patients have a better prognosis compared with patients with HPV-negative Head and Neck Squamous Cell Carcinoma (HNSCC), when treated similarly. Expression of tumor suppressor protein, known as p16, is highly correlated with infection with HPV in HNSCC. Accurate HPV assessment in head and neck cancers is becoming important as it significantly impacts clinical management. HPV status is considered the most important prognostic indicator in patients with head and neck cancer and p16 status is now included in the American Joint Committee on Cancer (AJCC) Staging System.

HPV-positive Oropharyngeal Squamous Cell Carcinoma is more sensitive to chemotherapy and radiotherapy than is HPV-negative Oropharyngeal Squamous Cell Carcinoma, which translates to a much better prognosis and survival, when treated with a combination of Cisplatin chemotherapy and Radiotherapy. This treatment however can be associated with substantial morbidity and lifelong toxicities such as dry mouth, difficulty swallowing, and loss of taste.Oropharynx

To address these toxicities, the authors conducted a prospective Phase II de-escalation study utilizing FDG-PET response criteria to select patients eligible for de-escalated radiotherapy. The researchers hypothesized that early swallow function and quality of life will improve with lower dose radiation. This study enrolled 59 patients (N=59) with Stage I-II (AJCC) p16-positive Oropharyngeal cancer, with FDG-avid disease and any smoking history. Patients with matted lymph nodes or history of head and neck surgery were excluded.

All enrolled patients had a pre-treatment FDG-PET/CT imaging and received weekly Carboplatin and Paclitaxel concurrently with planned radiotherapy at 70 Gy in 35 fractions. FDG-PET was repeated midway through treatment after 2 weeks at fraction 10. Patients who had tumors with lower metabolic activity before treatment and more than 50% reduction in Metabolic Tumor Volume after 2 weeks of treatment were de-escalated from the standard radiotherapy total dose of 70 Gy in 35 fractions, to a total dose of 54 Gy in 27 fractions. The median patient age was 60 years and baseline characteristics showed that both standard and de-escalated cohorts had similar patient demographics and pathology. At the planned interim analysis, early toxicity and Patient Reported Outcomes (PROs) were examined.

Fifty percent (50%) of the patients met de-escalation criteria and received the lower radiation dose, leading to 20-30% reductions in radiation exposure to sensitive structures in the head and neck prone to toxicities such as larynx, constrictors, oral cavity and salivary glands. De-escalation from the standard radiotherapy resulted in significantly less acute toxicity, and at one month after treatment, patients who received de-escalated therapy lost less weight as a percentage of baseline, compared to standard treatment group (6% versus 11%; P<0.001) and had improved videofluoroscopic swallowing function following treatment, and fewer patients required feeding tube placement during treatment.

The authors concluded that although the trial remains ongoing, mid-treatment FDG-PET response adaptation allows for approximately 50% of early stage p16 positive Oropharyngeal cancer patients to be de-escalated to a total dose of 54 Gy. This in turn can result in approximately 25% reduction in dose delivered to organs known to affect toxicity and quality of life, with significantly better objective measures of toxicity and numerically improved Patient Related Outcomes.

Early Toxicity and Patient Reported Outcomes From a Phase 2 Trial of FDG-PET Response-Based De-Escalated Definitive Radiotherapy for p16+ Oropharynx Cancer. Allen SG, Rosen BS, Aryal MP, et al. 2022 Multidisciplinary Head and Neck Symposium; February 24-26, 2022; Phoenix, AZ. Abstract 1.

NUBEQA® Combination Improves Overall Survival in Metastatic Hormone Sensitive Prostate Cancer

SUMMARY: Prostate cancer is the most common cancer in American men with the exclusion of skin cancer, and 1 in 9 men will be diagnosed with Prostate cancer during their lifetime. It is estimated that in the United States, about 268,490 new cases of Prostate cancer will be diagnosed in 2022 and 34,500 men will die of the disease. The development and progression of Prostate cancer is driven by androgens. Androgen Deprivation Therapy (ADT) or testosterone suppression has therefore been the cornerstone of treatment of advanced Prostate cancer and is the first treatment intervention.

The first-generation NonSteroidal Anti-Androgen (NSAA) agents such as EULEXIN® (Flutamide), CASODEX® (Bicalutamide) and NILANDRON® (Nilutamide) act by binding to the Androgen Receptor (AR) and prevent the activation of the AR and subsequent up-regulation of androgen responsive genes. They may also accelerate the degradation of the AR. These agents have a range of pharmacologic activity from being pure anti-androgens to androgen agonists. CASODEX® is often prescribed along with GnRH (Gonadotropin-Releasing Hormone) agonists for metastatic disease, or as a single agent second line hormonal therapy for those who had progressed on LHRH agonists.

NUBEQA® (Darolutamide) is a potent second-generation Androgen Receptor (AR) inhibitor with a new chemical structure and has a high affinity to the AR. NUBEQA® does not cross the blood-brain barrier and for this reason has a favorable safety and tolerability profile in prespecified adverse events such as seizures, when compared with other second-generation AR inhibitors such as ERLEADA® (Apalutamide) and XTANDI® (Enzalutamide). It has been associated with increased Overall Survival (OS) among patients with non-metastatic Castration-Resistant Prostate Cancer (CRPC) and has been approved by the FDA for this indication. Whether a combination of NUBEQA®, in combination with Androgen Deprivation Therapy (ADT), and Docetaxel would increase survival among patients with metastatic Hormone-Sensitive Prostate Cancer, is unknown.

ARASENS is an international, randomized, double-blind, placebo-controlled, Phase III trial, which evaluated the efficacy and safety of NUBEQA® (Darolutamide) added to Androgen Deprivation Therapy (ADT) and Docetaxel in patients with metastatic Hormone Sensitive Prostate Cancer. In this study, a total of 1306 patients were randomly assigned 1:1 to receive NUBEQA® (N=651) or placebo (N=655), both in combination with ADT and Docetaxel. All the patients received ADT (either a Luteinizing Hormone Releasing Hormone (LHRH} agonist or antagonist) or underwent Orchiectomy within 12 weeks before randomization and received six cycles of Docetaxel 75 mg/m2 IV given on Day 1 every 21 days, with Prednisone or Prednisolone. Patients received LHRH agonists along with a first-generation anti-androgen agent for at least 4 weeks before randomization to help prevent a tumor flare, and the anti-androgen agent was discontinued before randomization. Patients were then randomly assigned to receive either NUBEQA® 600 mg orally twice daily or matched placebo, and treatment was continued until disease progression or unacceptable toxicities.

Eligible patients had biopsy proven prostate cancer with bone metastases and had to be candidates for ADT and Docetaxel. Patients with regional lymph node involvement only (N1, below the aortic bifurcation) or if they had received ADT more than 12 weeks before randomization, second-generation Androgen Receptor pathway inhibitors, chemotherapy, or immunotherapy for prostate cancer before randomization, or radiotherapy within 2 weeks before randomization, were excluded. The median age was 67 years and both treatment groups were well balanced. All patients had metastatic disease at baseline, 78% of the patients had a Gleason score of 8 or greater, about 80% had bone metastases (Stage M1b) and 18% had visceral metastases (Stage M1c). The Primary end point was Overall Survival (OS) and Secondary end points included were time to Castration-Resistant Prostate Cancer, time to pain progression, symptomatic Skeletal Event-Free Survival and time to initiation of subsequent systemic antineoplastic therapy, as well as Safety. The median follow up for Overall Survival was 43 months.

The median Overall Survival was not estimable in the NUBEQA® group versus 48.9 months in the placebo group. The addition of NUBEQA® to the combination with ADT and Docetaxel reduced the risk of death by 32%, compared to the placebo group (HR=0.68; P<0.001). This OS benefit was noted across most subgroups. Further, the significant OS benefit with the addition of NUBEQA® was observed, despite receipt of subsequent life-prolonging systemic therapies such as different Androgen-Receptor pathway inhibitors by 75.6% of patients in the placebo control group. The OS at 4 years was 62.7% in the NUBEQA® group and 50.4% in the placebo group.

With regard to Secondary endpoints, the addition of NUBEQA® to ADT and Docetaxel demonstrated consistent benefits. The time to development of Castration-Resistant Prostate Cancer was significantly longer in the NUBEQA® group (HR=0.36; P<0.001), the time to pain progression was also significantly longer in the NUBEQA® group (HR=0.79; P=0.01), as well as symptomatic Skeletal Event-Free Survival (HR=0.61; P<0.001). Further, the time to the initiation of subsequent systemic antineoplastic therapy was also significantly longer in the NUBEQA® group (HR=0.39; P<0.001). Adverse events were similar in the two groups.

The authors concluded that among patients with metastatic Hormone Sensitive Prostate Cancer, the addition of NUBEQA® to Androgen Deprivation Therapy and Docetaxel resulted in significantly longer Overall Survival, as well as improvement in key Secondary end points, with no increase in adverse events.

Darolutamide and Survival in Metastatic, Hormone-Sensitive Prostate Cancer. Smith MR, Hussain Saad F, et al. for the ARASENS Trial Investigators. NEJM. February 17, 2022. DOI: 10.1056/NEJMoa2119115.