Category: Immuno Oncology

Survival Benefit with KEYTRUDA® After Locally Ablative Therapy (LAT) for Oligometastatic NSCLC

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SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2019, about 228,150 new cases of lung cancer will be diagnosed and 142,670 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.

It is estimated that approximately 7% of patients with NSCLC present with a limited number of metastatic foci (oligometastatic). Several retrospective studies have shown that the use of Locally Ablative Therapy (LAT) to all sites of disease in oligometastatic NSCLC is associated with a significant improvement in Progression Free Survival (PFS) and Overall Survival (OS), when compared with historical data. Preclinical evidence had suggested that chemotherapy and radiotherapy may upregulate PD-L1 expression in tumor cells. Therefore, incorporating immunotherapy along with LAT has been an area of active research. In the PACIFIC trial, consolidation therapy with PD-L1 inhibitor IMFINZI® (Durvalumab), following chemoradiation, significantly improved PFS and OS among patients with locally advanced NSCLC suggesting that there is a strong biological rationale for the use of immunotherapy in patients with minimal residual disease state.

KEYTRUDA® (Pembrolizumab) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor 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. The primary objective of this study was to evaluate whether the addition of KEYTRUDA® after Locally Ablative Therapy (LAT) improves outcomes among patients with oligometastatic NSCLC, compared with historical data.

The authors conducted a single arm Phase II trial at an academic referral cancer center, and 51 eligible patients with oligometastatic NSCLC (no more than 4 metastatic sites) were enrolled. Enrolled patients had oligometastatic disease at diagnosis (synchronous disease) or who developed oligometastatic disease after initial definitive therapy (metachronous disease). There was no limit on the number of prior therapies, although patients could not have received prior therapy with a Programmed Death 1 (PD-L1) inhibitor. Any form of Locally Ablative Therapy (LAT) was acceptable and LATs included Surgery, Chemoradiotherapy, Stereotactic radiotherapy, and/or Interventional ablation. Forty five of the 51 patients enrolled received KEYTRUDA® within 4 to 12 weeks of completing LAT. Patients received KEYTRUDA® 200 mg IV every 21 days, for 8 cycles and were allowed to continue therapy for a total of 16 cycles in the absence of progressive disease or untoward toxicities. The median age was 64 years and patients were eligible regardless of their PD-L1 or molecular target status. Thirty-two patients had adequate tissue for assessment of PD-L1 status, and 29 patients had adequate tissue for assessment of CD8 T-cell infiltration. In patients undergoing testing, 34% had results positive for PD-L1 (1% or more) and 52% had CD8 T-cell infiltration of greater than 2.5%. Patients received a median of 11 cycles of KEYTRUDA®.

The two Primary efficacy end points were Progression Free Survival (PFS) from the start of Locally Ablative Therapy (PFS-L) and PFS from the start of KEYTRUDA® therapy (PFS-P). This study was powered for comparison with historical data on the first efficacy end point. Secondary outcomes included Overall Survival, Safety, and Quality of Life, as measured by the Functional Assessment of Cancer Therapy–Lung (FACT-L) instrument.

After a median follow-up of 23.2 months for surviving patients, the median PFS from the start of Locally Ablative Therapy (PFS-L) was 19.1 months, which was a statistically significant improvement from the historical median of 6.6 months (P=0.005). The median PFS from the start of KEYTRUDA® therapy (PFS-P) was 18.7 months. The mean Overall Survival rate at 12 months was 90.9% and at 24 months was 77.5%. The Progression Free Survival from the start of Locally Ablative Therapy (PFS-L) was not influenced by PD-L1 expression or CD8 T-cell tumor infiltration. Quality of Life as measured by the FACT-L scores at cycles 8 and 16 were not significantly different from FACT-L scores at baseline.

The authors concluded that KEYTRUDA® after Locally Ablative Therapy for oligometastatic NSCLC was associated with a clinically and statistically significant improvement in Progression Free Survival, compared with historical data, without a decrement in Quality of Life. They added that the Overall Survival data is encouraging but will require further follow up. Pembrolizumab After Completion of Locally Ablative Therapy for Oligometastatic Non–Small Cell Lung Cancer: A Phase 2 Trial. Bauml JM, Mick R, Ciunci C, et al. JAMA Oncol. Published online July 11, 2019. doi:10.1001/jamaoncol.2019.1449

FDA Approves KEYTRUDA® for Advanced Small Cell Lung Cancer

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SUMMARY: The FDA on June 17, 2019 granted accelerated approval to KEYTRUDA® (Pembrolizumab) for patients with metastatic Small Cell Lung Cancer (SCLC) with disease progression on or after Platinum-based chemotherapy, and at least one other prior line of therapy. The American Cancer Society estimates that for 2019 about 228,150 new cases of lung cancer will be diagnosed and about 142,670 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Small cell lung cancer (SCLC) accounts for approximately 13-15% of all lung cancers, and is aggressive. Patients with SCLC are often treated with platinum based chemotherapy as first-line treatment, and the tumor response rates are as high as 60-80%. However, only 20% of patients with Limited Stage SCLC are cured, and majority of the patients relapse within months of completing initial therapy. Patients often receive HYCAMTIN® (Topotecan) for recurrent or progressive SCLC (second-line treatment) and after failure on second-line therapy, treatment options are limited. The 5 year survival rate for Extensive Stage SCLC is less than 5%, with a median survival of 9-10 months from the time of diagnosis.

KEYTRUDA® is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor 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.

The present FDA approval was based on pooled data from two Basket studies, KEYNOTE-158 (cohort G) and KEYNOTE-028 (cohort C1), which are two multicenter, multi-cohort, non-randomized, open-label trials, evaluating KEYTRUDA® in patients with SCLC, who had disease progression on or after platinum-based chemotherapy and at least one other prior line of therapy. In Basket trials, patients with different tumor histologies receive a single treatment and have a single biomarker. Among the 83 patients evaluated in both these studies for efficacy, 64% received two prior lines of therapy and 36% received three or more lines of therapy; 60% received prior thoracic radiation therapy; 51% received prior radiation therapy to the brain. Patients in the KEYNOTE-028 were required to have tumors expressing PD-L1, whereas PD-L1 positivity was not required for KEYNOTE-158. Patients in the KEYNOTE-028 study received KEYTRUDA® 10 mg/kg IV every 2 weeks (N=19), whereas those in KEYNOTE-158 received KEYTRUDA® 200 mg IV every 3 weeks (N=64). Treatment was continued until documented disease progression, unacceptable toxicity, or a maximum of 24 months. The major efficacy outcome measures included Objective Response Rate (ORR) and Duration of Response (DOR).

Treatment with KEYTRUDA® resulted in an Overall Response Rate of 19%, with a Complete Response Rate of 2% and a Partial Response Rate of 17%. Of the responding patients, 94% had a Duration of Response (DOR) of 6 months or longer, 63% had a DOR of 12 months or longer, and 56% had a DOR of 18 months or longer. Responses ranged from 4.1 to over 35.8 months. Adverse Events were similar to those occurring in patients with other solid tumors who received KEYTRUDA® as a single agent and the common adverse reactions included fatigue, decreased appetite, cough, nausea and constipation.

It was concluded that this new indication marks the first FDA approval for KEYTRUDA® in Small Cell Lung Cancer, and provides an additional treatment option for patients with advanced stage disease, based on clinical response rates. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-pembrolizumab-metastatic-small-cell-lung-cancer

Late Breaking Abstract – ASCO 2019 Front-Line Keytruda® Monotherapy for Patients with Advanced Gastric or Gastroesophageal Junction Adenocarcinoma

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SUMMARY: The American Cancer Society estimates that in the US, about 27,510 cases of Gastric Cancer will be diagnosed in 2019 and about 11,140 people will die of the disease. The average age at diagnosis is 68 years and Gastric Cancer is one of the leading causes of cancer-related deaths in the world. Risk factors for gastric cancer include age, gender, ethnicity, geography and infection with Helicobacter pylori. 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 (GE) Adenocarcinoma have advanced disease at the time of initial presentation and have limited therapeutic options with little or no chance for cure. These patients frequently are treated with Platinum containing chemotherapy along with a Fluoropyrimidine and, if appropriate, HER2/neu-targeted therapy. This can however be associated with significant toxicities impacting patient’s quality of life.

KEYTRUDA® (Pembrolizumab) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor 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. KEYTRUDA® in the Phase II KEYNOTE-059 trial demonstrated promising antitumor activity and durable responses in patients with advanced Gastric/GastroEsophageal Junction cancer, who had progressed on more than 2 lines of therapy, with higher Objective Response Rates noted in patients with PD-L1-positive tumors.

KEYNOTE-062 is a randomized, phase III controlled study in which KEYTRUDA® monotherapy was compared to standard chemotherapy as first line treatment, in select patients with advanced Gastric or GastroEsophageal Junction (GEJ) Adenocarcinoma. This trial enrolled 763 newly diagnosed patients of whom 69% had Gastric Adenocarcinoma cancer and 30% had GEJ Adenocarcinoma. Patients were randomized 1:1:1 to receive KEYTRUDA® 200 mg IV every 3 weeks for up to 2 years (N=256), KEYTRUDA® plus Cisplatin 80 mg/m2 IV every three weeks along with either 5-Fluorouracil 800 mg/m2 daily on Days 1-5 every three weeks or XELODA® (Capecitabine) 1000 mg/m2 twice a day on Days 1-14 every three weeks (N=257 ) or placebo plus Cisplatin and either 5-FU or XELODA® given at a similar dose and schedule as the second group (N=250). The median patient age was 62 years and PD-L1 expression was assessed by Combined Positive Score (CPS). The Primary endpoints were Overall Survival (OS) in patients whose tumors expressed PD-L1 CPS 1 or more and CPS 10 or more in the KEYTRUDA® monotherapy group and in combination with chemotherapy group, as well as Progression Free Survival (PFS) in patients whose tumors expressed PD-L1 CPS 1 or more in the combination arm. Secondary endpoints included Overall Response Rate (ORR) and Duration of Response (DOR) in patients whose tumors express PD-L1 CPS 1 or more. In the current trial, all patients had a PD-L1 CPS of at least 1, and 281 patients (37%) had a PD-L1 CPS score of 10 or more. The median follow-up was 11.3 months.

The trial met its Primary endpoint and among patients with a PD-L1 CPS of 1 or more, Overall Survival was noninferior to chemotherapy. The median Overall Survival was 10.6 months in the KEYTRUDA® monotherapy group compared with 11.1 months in the chemotherapy group (HR=0.91). Among patients with a PD-L1 CPS 10 or more, Overall Survival with KEYTRUDA® was superior to chemotherapy. The median Overall Survival was 17.4 months for those receiving KEYTRUDA® compared with 10.8 months for those receiving chemotherapy. After 2 years, 39% of people taking KEYTRUDA® were alive compared with 22% of those taking chemotherapy (HR=0.69). The OS and PFS rates for the combination of KEYTRUDA® and chemotherapy were comparable with those of chemotherapy alone, regardless of PD-L1 CPS. The efficacy outcomes were not influenced by age, tumor size or location, histological subtype, number of metastatic sites and prior gastrectomy status.

It was concluded that KEYTRUDA® monotherapy is noninferior to chemotherapy for OS among patients with PD-L1 CPS 1 or more. There was however a clinically meaningful improvement in OS among patients with PD-L1 CPS 10 or more. Further, there was a more favorable safety profile for KEYTRUDA® over chemotherapy, making this a more desirable treatment option for elderly patients, for whom platinum based chemotherapy may not be appropriate. Pembrolizumab with or without chemotherapy versus chemotherapy for advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma: The phase III KEYNOTE-062 study. Tabernero J, Van Cutsem E, Bang Y-J, et al. J Clin Oncol 37, 2019 (suppl; abstr LBA4007)

Late Breaking Abstract – ASCO 2019 XTANDI® Improves Overall Survival in Metastatic Hormone-Sensitive Prostate Cancer

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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 174,650 new cases of Prostate cancer will be diagnosed in 2019 and 31,620 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 a nonsteroidal oral anti-androgen, that 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. XTANDI® (Enzalutamide) is an orally administered, second-generation, anti-androgen, with no reported agonistic effects. It competitively inhibits androgens and AR binding to androgens as well as AR nuclear translocation and interaction with DNA. It thus inhibits several steps in the AR signaling pathway and was designed to overcome acquired resistance to first-generation nonsteroidal anti-androgens. Previously published studies have shown that XTANDI® improved Overall Survival in Castration-Resistant Prostate Cancer, regardless of whether it was used before or after Docetaxel chemotherapy. The benefits of adding Docetaxel or ZYTIGA® (Abiraterone) to testosterone suppression in men with metastatic, hormone-sensitive Prostate cancer have been established in randomized clinical trials.XTANDI - Mechanism-of-Action

ENZAMET (Enzalutamide in First Line Androgen Deprivation Therapy for Metastatic Prostate Cancer) is an open-label, international, randomized, Phase III trial, conducted to evaluate the benefits of adding XTANDI® to initial standard treatment of Androgen Deprivation Therapy (ADT) with or without early Docetaxel, among patients with metastatic hormone-sensitive Prostate cancer.

A total of 1125 men with metastatic hormone-sensitive Prostate cancer were randomly assigned 1:1 to receive either ADT plus XTANDI® or NonSteroidal Anti-Androgens (NSAA). ADT consisted of parenteral injection of a testosterone-suppressing agent (such as Goserelin, Leuprolide, or Degarelix) with either a 160 mg dose of XTANDI® daily or one of the standard NSAA’s such as CASODEX®, EULEXIN® or NILANDRON®. Of the 1,125 men enrolled in the trial, 503 men received early doses of Docetaxel, and 602 did not. The decision to initiate early treatment with Docetaxel was at the treating physician’s discretion and was administered at 75 mg/m2 IV without prednisone every 3 weeks for a maximum of six cycles. Randomized patients were stratified according to the volume of disease (High Risk- defined as the presence of visceral metastases or at least four bone lesions with at least one lesion located beyond the vertebral bodies and pelvis or low), planned use of early Docetaxel, planned use of bone antiresorptive therapy, and score on ACE-27 (Adult Comorbidity Evaluation 27), with no coexisting conditions rated as 0, mild rated as 1, moderate rated as 2, and severe or multiple conditions rated as 3. The mean age was 68 years, 45% of patients received early Docetaxel as planned treatment and over 50% of the patients had high volume disease. The Primary end point was Overall Survival (OS) and Secondary end points included Progression Free Survival (PFS) as determined by the PSA level, clinical PFS, and adverse events. The median follow up was 34 months.

At the time of the first interim analysis, there was a 33% reduction in the risk of death in the XTANDI® group compared to the standard treatment group ((HR=0.67; P<0.002) and the estimated Overall Survival at 3 years were 80% in the XTANDI® group and 72% in the standard-of-care group. The addition of XTANDI® also improved PSA Progression Free Survival with a 61% reduction in the risk of PSA progression (HR=0.39; P<0.001) and 60% improvement in clinical PFS (HR=0.40; P<0.001). The effects of XTANDI® on clinical PFS were noted in all predefined subgroups, including those with early Docetaxel treatment. Among the patient group who also received early Docetaxel treatment, there was however no significant improvement in Overall Survival. Adding XTANDI® to standard ADT was associated with a higher frequency of toxic effects, especially peripheral neuropathy, associated with the concomitant use of Docetaxel, fatigue and slightly higher risk of seizures compared to standard therapy, and more patients discontinued treatment due to adverse events in the XTANDI® group.

It was concluded that XTANDI® was associated with significantly longer Progression Free Survival and Overall Survival than standard intervention, in men with metastatic, hormone-sensitive Prostate cancer receiving Androgen Deprivation Therapy. Patients who received early Docetaxel treatment, however did not have significant survival benefit. The authors added that ENZAMET is the first metastatic hormone-sensitive Prostate cancer trial to report Overall Survival data of an androgen receptor inhibitor (XTANDI®), and outcomes among a set of patients who also concurrently received Docetaxel. Enzalutamide with Standard First-Line Therapy in Metastatic Prostate Cancer. Davis ID, Martin AJ, Stockler MR, et al. for the ENZAMET Trial Investigators and the Australian and New Zealand Urogenital and Prostate Cancer Trials Group. June 2, 2019. DOI: 10.1056/NEJMoa1903835

KEYTRUDA® versus Chemotherapy as Second-Line Treatment for Advanced Esophageal Cancer

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SUMMARY: The American Cancer Society estimates that in 2019, about 17,650 new cases of esophageal cancer will be diagnosed in the US and about 16,080 individuals will die of the disease. It is the sixth most common cause of global cancer death. Squamous Cell Carcinoma is the most common type of cancer of the esophagus among African Americans, while Adenocarcinoma is more common in caucasians. About 20% of patients survive at least 5 years following diagnosis. Patients with advanced esophageal cancer following progression on first line chemotherapy have limited treatment options and have a poor prognosis.

KEYTRUDA® (Pembrolizumab) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor 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. KEYTRUDA® in the Phase II KEYNOTE-180 study demonstrated durable responses among heavily pretreated patients with advanced metastatic Adenocarcinoma or Squamous Cell Carcinoma of the Esophagus as well as tumors with PD-L1 Combined Positive Score (CPS) of 10 or higher.

KEYNOTE-181 is a global, open-label, Phase III study which included 628 patients with advanced or metastatic adenocarcinoma or squamous cell carcinoma of the esophagus, or Siewert Type I adenocarcinoma of the esophagogastric junction that had progressed after first-line standard therapy. [Adenocarcinomas arising in the vicinity of the EsophagoGastric Junction are classified (Siewert classification) into adenocarcinoma of the distal esophagus (Type I), true carcinoma of the cardia (Type II) and subcardial carcinoma (Type III)].

Patients were randomized 1:1 to KEYTRUDA® 200 mg Q3W for up to 35 cycles (approximately2 years) or investigator’s choice chemotherapy with Docetaxel 75 mg/m2 IV on day 1 of each 21 day cycle, OR Paclitaxel 80-100 mg/m2 IV on days 1, 8 and 15 of each 28-day cycle, OR Irinotecan 80 mg/m2 IV on day 1 of each 14-day cycle. Randomization was stratified by histology and region (Asia vs rest of world). The majority of patients (N=401; 64%) had Squamous Cell Carcinoma (SCC), and 222 patients had PD-L1 Combined Positive Score (CPS) of 10 or higher. The three Primary end points were Overall Survival (OS) in patients with SCC, patients with PD-L1 CPS of 10 or higher and Intent-To- Treat populations. The median follow up was 7 months.

It was noted that among the patients with a PD-L1 CPS of 10 or higher (35% of the study population), the median Overall Survival was 9.3 months with KEYTRUDA® versus 6.7 months with chemotherapy (HR=0.69; P=0.0074). The 12-month survival rate in this group was 43% versus 20% respectively. In the Squamous Cell Carcinoma subgroup (N=401), the median Overall Survival was 8.2 months with KEYTRUDA® versus 7.1 months with chemotherapy (HR=0.78; P=0.0095). These differences favoring KEYTRUDA® however, did not meet the study’s prespecified statistical boundary. In the Intent-To- Treat population, the median Overall Survival was 7.1 months in each treatment group (HR=0.89; P=0.0560), and was not statistically significant. The Progression Free Survival at 12 months among patients with a PD-L1 CPS of 10 or higher was 21% versus 7% for KEYTRUDA® and chemotherapy, respectively. Further, in this patient group, KEYTRUDA® more than doubled the Response Rates than those achieved with chemotherapy, with a longer median duration of response (9.3 versus 7.7 months respectively). Fewer patients had any grade drug-related adverse events with KEYTRUDA®, compared with chemotherapy.

The authors concluded that KEYTRUDA® significantly improved Overall Survival compared with chemotherapy, as second line therapy for patients with advanced esophageal cancer, with PD-L1 CPS of 10 or higher and also had a more favorable safety profile. They added that these data support KEYTRUDA® as a new second line standard of care for esophageal cancer with PD-L1 CPS of 10 or higher. A Phase III study of KEYTRUDA® plus chemotherapy as first line therapy for advanced esophageal cancer is underway. Pembrolizumab versus chemotherapy as second-line therapy for advanced esophageal cancer: Phase III KEYNOTE-181 study. Kojima T, Muro K, Francois E, et al. J Clin Oncol 37, 2019 (suppl 4; abstr 2)

FDA Lowers PD-L1 Expression Threshold for KEYTRUDA® and Expands Indication for Frontline Treatment of NSCLC

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SUMMARY: The FDA on April 11, 2019, approved KEYTRUDA® (Pembrolizumab) for the first-line treatment of patients with Stage III Non-Small Cell Lung Cancer (NSCLC) who are not candidates for surgical resection or definitive chemoradiation, as well as those with metastatic NSCLC. Patients’ tumors must have no EGFR or ALK genomic aberrations and express PD-L1 (Tumor Proportion Score-TPS of 1% or more), as determined by an FDA-approved test. Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2019 about 228,150 new cases of lung cancer will be diagnosed and 142,670 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.

KEYTRUDA® (Pembrolizumab) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor 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. High level of Programmed Death-Ligand 1 (PD-L1) expression is defined as membranous PD-L1 expression on at least 50% of the tumor cells, regardless of the staining intensity. It is estimated that based on observations from previous studies, approximately 25% of the patients with advanced NSCLC have a high level of PD-L1 expression, and high level of PD-L1 expression has been associated with significantly increased response rates to KEYTRUDA®. The FDA approved KEYTRUDA® for the first-line treatment of advanced NSCLC with high PD-L1 expression (Tumor Proportion Score of 50% or more), based on KEYNOTE-024 trial, as well as in combination with Pemetrexed and Carboplatin, as first-line treatment of patients with metastatic non-squamous NSCLC, based on KEYNOTE-021 study. It is also indicated for previously treated advanced NSCLC with a much lower level of PD-L1 expression such as PD-L1 Tumor Proportion Score of 1% or higher, based on KEYNOTE-010 trial.Unleashing-T-Cell-Function-with-PD-1-and-PD-L1-Antibodies

KEYNOTE-042 is a large, international, multicenter, randomized phase III trial in which 1274 patients with untreated locally advanced or metastatic NSCLC were randomly assigned to KEYTRUDA® or chemotherapy with Paclitaxel plus Carboplatin or Pemetrexed plus Carboplatin. In this study, both squamous and non-squamous cancers with PD-L1 Tumor Proportion Score (TPS) of 1% or more were included, but tumors with sensitizing Epidermal Growth Factor Receptor (EGFR) or Anaplastic Lymphoma Kinase (ALK) mutations cancers with genetic changes, that could be treated with targeted therapies such as EGFR and ALK inhibitors, were excluded. Eligible patients were randomly assigned in a 1:1 to receive either KEYTRUDA® 200 mg IV every 3 weeks for up to 35 cycles or investigator’s choice of up to 6 cycles of chemotherapy with Paclitaxel plus Carboplatin or Pemetrexed plus Carboplatin, with optional Pemetrexed maintenance for non-squamous NSCLC. Patients were divided into 3 treatment groups based on their PD-L1 Tumor Proportion Score (TPS): TPS 50% or more (N=599), TPS 20% or more (N=818), and TPS 1% or more (N=637). Each PD-L1 expression group had equal numbers of patients receiving KEYTRUDA® and chemotherapy. The Primary end points were Overall Survival (OS) in patients with TPS 50% or more, 20% or more, and 1% or more.

At a median follow up of 12.8 months, 13.7% of patients were still receiving KEYTRUDA® compared with 4.9% on Pemetrexed maintenance therapy. It was noted that KEYTRUDA® was significantly superior to chemotherapy in all PD-L1 expression subsets. In patients with a PD-L1 TPS 50% or more, the median OS with KEYTRUDA® was 20 months versus 12.2 months for chemotherapy (HR=0.69, P=0.0003), for patients with PD-L1 TPS 20% or more, the median OS was 17.7 months versus 13 months respectively (HR=0.77, P=0.002), and for those with PD-L1 TPS 1% or more, the median OS was 16.7 months versus 12.1 months respectively (HR=0.81, P = 0.0018). The Response Rates (RR) were also higher among patients who received KEYTRUDA®, with RR of 39.5% for KEYTRUDA® versus 32% for chemotherapy in patients with a TPS 50% or more, 33.4% and 28.9% respectively in patients with TPS 20% or more and 27.3% and 26.5%, respectively, among patients with TPS of 1% or more. The duration of response was also superior with KEYTRUDA® in all three PD-L1 subgroups compared to chemotherapy (20.2 months versus 8-11 months). Patients receiving KEYTRUDA® experienced fewer severe Adverse Events, compared with chemotherapy (17.8% versus 41%).

The authors concluded that this is the largest clinical trial of KEYTRUDA® as a stand-alone therapy, and is the first study with a Primary end point of OS to demonstrate superiority of KEYTRUDA® over platinum-based chemotherapy, in patients with previously untreated locally advanced/metastatic NSCLC, without sensitizing EGFR or ALK alterations and a PD-L1 TPS of 1% or more. These data confirmed the benefit of KEYTRUDA® monotherapy as a standard first-line treatment, for PD-L1-expressing locally advanced Stage III as well as metastatic NSCLC. KEYTRUDA® monotherapy is now a new treatment option for more patients with NSCLC, including those for whom combination therapy may not be appropriate. Pembrolizumab versus chemotherapy for previously untreated, PD-L1-expressing, locally advanced or metastatic non-small-cell lung cancer (KEYNOTE-042): a randomised, open-label, controlled, phase 3 trial. Mok TS, Wu Y-L, Kudaba I, et al. The Lancet. Published: April 04, 2019. DOI: https://doi.org/10.1016/S0140-6736(18)32409-7

AACR Late-Breaking Research Predicting Response to Anti-PD1/PDL1 Therapy beyond Tumor Mutational Burden

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SUMMARY: Immunotherapy with checkpoint inhibitors such as anti-PD1/PDL1 antibodies, is rapidly moving to the forefront of cancer treatment. These agents include PD1 targeted therapies such as KEYTRUDA® (Pembrolizumab), OPDIVO® (Nivolumab) and LIBTAYO® (Cemiplimab-rwlc) and PDL1 targeted therapies such as TECENTRIQ® (Atezolizumab), IMFINZI® (Durvalumab) and BAVENCIO® (Avelumab). Treatment with checkpoint inhibitors given as a single agent or in combination with chemotherapy has resulted in significant survival benefit in a variety of solid tumors, as well as hematologic malignancies. The efficacy of checkpoint inhibitors however varies considerably across different cancer types. Understanding tumors and their microenvironment and identifying the underlying variables that predict response to anti-PD1/PDL1 antibodies, has been challenging.

Tumor Mutational Burden (TMB) has recently emerged as a potential biomarker for immunotherapy with anti PD-1/PDL1 antibodies. TMB can be measured using Next-Generation Sequencing (NGS) and is defined as the number of somatic coding base substitutions and short insertions and deletions (indels), per megabase of genome examined. Several studies have incorporated Tumor Mutational Burden (TMB) as a biomarker, using the validated cutoff of TMB of 10 or more mutations/megabase as High, and less than 10 mutations/megabase, as Low. Drawbacks with TMB include sample consumption, higher attrition rate due to sample quality and quantity, and lack of standardization for the different TMB testing assays, with the definition of High TMB varying across studies from 7.4 or more to 20 mutations/megabase.

The Cancer Genome Atlas (TCGA), a landmark cancer genomics program, is a joint effort between the National Cancer Institute and the National Human Genome Research Institute. This program began in 2006 and has molecularly characterized over 20,000 primary cancers and matched normal samples, across 33 different cancer types. After 12 years and contributions from over 11,000 patients, TCGA has deepened our understanding of the molecular basis of cancer, changed the way cancer patients are managed in the clinic, established a rich genomics data resource for the research community and helped advance health and science technologies.

The authors in this study systematically analyzed Whole Exome Sequencing (WES) and RNA sequencing (RNAseq) data of 10,000 patients from the Cancer Genome Atlas, and the Overall Response Rate (ORR) to anti-PD1/PDL1 therapy of 21 different cancer types obtained from previous clinical trials. The researchers took into consideration more than 30 different variables belonging to three distinct classes: a) those associated with tumor neoantigen landscape (Tumor Mutational Burden-TMB) b) tumor microenvironment and inflammation, and c) the checkpoint inhibitor targets (PD1/PDL1). The performance of each of these variables and their combinations was then evaluated in predicting the ORR to anti-PD1/PDL1 therapy.

It was noted that the most important predictor of response to anti-PD1/PDL1 therapy across cancer types was CD8+ T-cell abundance in the tumor microenvironment, followed by the Tumor Mutational Burden, and a high PD1 gene expression in each cancer type in a fraction of samples. These three top predictors encompassed the three distinct classes considered in this analysis, and their combination was highly predictive of the ORR to anti-PD1/PDL1 therapy, and was able to explain more than 80% of the variance observed across different tumor types.

The authors concluded that in this first systemic evaluation of the different variables associated with PD1/PDL1 therapy response across different tumor types, the three top predictors mentioned above can explain most of the observed cross-cancer response variability. Combining tumor mutational burden, CD8+ T-cell abundance and PD1 mRNA expression accurately predicts response to anti-PD1/PDL1 therapy across cancers. Lee JS and Ruppin E. Presented at: 2019 AACR Annual Meeting; March 29 to April 3, 2019; Atlanta, GA.LB-017/9

Immune Checkpoint Inhibitor Combination Efficacious in High-Grade Neuroendocrine Tumors

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SUMMARY: It is estimated that in the United States, more than 12,000 people are diagnosed with a Neuroendocrine tumor each year. NeuroEndocrine Tumors (NETs) arise from cells of the endocrine and nervous systems and produce biogenic amines and polypeptide hormones. NETs can be clinically symptomatic (functioning) or silent (nonfunctioning). The incidence is higher in African-Americans and is most frequently diagnosed in the small intestine, appendix, rectum, lungs and bronchi. The most common type of malignant gastrointestinal NETs originate in the midgut (jejunoileum and the proximal colon) and often metastasize to the mesentery, peritoneum and liver. NETs may be sporadic or may be a component of inherited genetic syndromes such as Multiple Endocrine Neoplasia (MEN) types 1 and 2. Majority of the NETs are nonfunctioning and are diagnosed incidentally but are clinically symptomatic following spread to the liver. Most NETs are classified based on tumor differentiation into 1) Well-differentiated, Low-grade (G1) 2) Well-differentiated, Intermediate-grade (G2) and 3) Poorly differentiated, High-grade (G3). Tumor differentiation and tumor grade often correlate with mitotic count and Ki-67 proliferation index. Even though surgery is curative when the tumor is detected early, this is often not the case, as most patients present with metastatic disease at the time of diagnosis.

OPDIVO® (Nivolumab) is a fully human, immunoglobulin G4 monoclonal antibody that binds to the PD-1 receptor and blocks its interaction with PD-L1 and PD-L2, whereas YERVOY® (Ipilimumab) is a fully human immunoglobulin G1 monoclonal antibody that blocks Immune checkpoint protein/receptor CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4, also known as CD152). Blocking the Immune checkpoint proteins unleashes the T cells, resulting in T cell proliferation, activation and a therapeutic response. Immune checkpoint blockade with monoclonal antibodies such as OPDIVO® and YERVOY® has revolutionized the treatment of multiple cancers. Previously published studies have demonstrated successful patient outcomes across various tumor types, when treated with a combination of CTLA-4 and PD-1 inhibitors. However, it has remained unclear whether these agents can benefit those with rare, metastatic solid tumors. The investigators therefore launched the DART trial to fulfill this unmet need.

SWOG S1609 Dual Anti-CTLA-4 & Anti-PD-1 blockade in Rare Tumors (DART) is the first NCI-funded prospective, open-label, rare tumor immunotherapy basket study. Basket trials involve single treatment and single biomarker, different histologies, placed in multiple groups or baskets. These trials are an efficient way for screening experimental therapeutics across multiple patient populations.

In this phase II trial which included 37 different types of rare tumors, patients received YERVOY® 1 mg/kg IV every 6 weeks along with OPDIVO® 240 mg IV every 2 weeks. The Primary endpoint was Overall Response Rate (ORR) and Secondary endpoints included Progression Free Survival (PFS), Overall Survival (OS), Stable disease more than 6 months, and toxicity. This publication included a cohort of 33 eligible patients with Neuroendocrine tumors. Pancreatic Neuroendocrine tumors are currently being evaluated in a separate cohort within the trial. More than half of the patients (58%) had high-grade disease, and the most common tumor sites were gastrointestinal-non pancreatic (45%) and lung (18%). Enrolled patients had received a median of 2 prior lines of therapy.

The Overall Response Rate was 24% with 3% Complete Responses and 21% Partial Responses. Patients with high-grade Neuroendocrine cancer had a 42% Response Rate, whereas the Response Rate was 0% in low/intermediate grade tumors (P=0.01), independent of primary site. The authors hypothesized that the high response rate among those with high-grade Neuroendocrine carcinomas may be related to a higher Tumor Mutational Burden, which is an indicator of better response to immunotherapy. The 6-month PFS was 30% and the median OS was 11 months (historically, it has been around 10% and 3 months respectively). The most common toxicities were fatigue (30% of patients) and nausea (27%) and the most common grade 3/4 immune-related Adverse Events were ALT elevation in 9% of patients.

It was concluded that YERVOY® plus OPDIVO® combination was well tolerated with a 42% ORR in patients with high-grade Neuroendocrine cancer, regardless of primary site. The authors based on this study pointed out that, clinical trials are feasible even in rare tumors. A Phase II basket trial of dual anti-CTLA-4 and anti-PD-1 blockade in rare tumors (DART) S1609: The neuroendocrine cohort. Patel SP, Othus M, Chae YK, et al. Presented at: 2019 AACR Annual Meeting; March 29 to April 3, 2019; Atlanta, GA.

FDA Approves TECENTRIQ® and ABRAXANE® Combination for Advanced Triple Negative Breast Cancer

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SUMMARY: The FDA on March 8, 2019 granted accelerated approval to TECENTRIQ® (Atezolizumab) in combination with ABRAXANE® (Paclitaxel protein-bound) for adult patients with unresectable locally advanced or metastatic Triple Negative Breast Cancer (TNBC) whose tumors express PD-L1 (PD-L1 stained tumor-infiltrating immune cells [IC] of any intensity covering 1% or more of the tumor area), as determined by an FDA-approved test. The FDA also approved the VENTANA PD-L1 (SP142) Assay as a companion diagnostic device for selecting TNBC patients for TECENTRIQ®. 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 268,600 new cases of female breast cancer will be diagnosed in 2019 and about 41,760 women will die of the disease.

Triple Negative Breast Cancer (TNBC) is a heterogeneous, molecularly diverse group of breast cancers and are ER (Estrogen Receptor), PR (Progesterone Receptor) and HER2 (Human Epidermal Growth Factor Receptor-2) negative. TNBC accounts for 15-20% of invasive breast cancers, with a higher incidence noted in young patients. It is usually aggressive, and tumors tend to be high grade and patients with TNBC are at a higher risk of both local and distant recurrence. Those with metastatic disease have one of the worst prognoses of all cancers with a median Overall Survival of 13 months. The majority of patients with TNBC who develop metastatic disease do so within the first 3 years after diagnosis, whereas those without recurrence during this period of time have survival rates similar to those with ER-positive breast cancers. The lack of known recurrent oncogenic drivers in patients with metastatic TNBC, presents a major therapeutic challenge. Nonetheless, patients with TNBC often receive chemotherapy in the neoadjuvant, adjuvant or metastatic settings and approximately 30-40% of patients achieve a pathological Complete Response (pCR) in the neoadjuvant setting. Those who do not achieve a pathological Complete Response tend to have a poor prognosis. It therefore appears that there are subsets of patients with TNBC who may be inherently insensitive to cytotoxic chemotherapy. Three treatment approaches appear to be promising and they include immune therapies, PARP inhibition and inhibition of PI3K pathway. Previously published studies have shown that tumor-infiltrating lymphocytes were associated with clinical benefit, when treated with chemotherapy and immunotherapy, in patients with TNBC, and improved clinical benefit was observed in patients with immune-enriched molecular subtypes of metastatic TNBC.

TECENTRIQ® (Atezolizumab) is an anti PD-L1 monoclonal antibody, designed to directly bind to PD-L1 expressed on tumor cells and tumor-infiltrating immune cells, thereby blocking its interactions with PD-1 and B7.1 receptors, and thus enabling the activation of T cells. Single-agent TECENTRIQ® is presently approved for the treatment of metastatic Urothelial carcinoma and Non Small Cell Lung Cancer (NSCLC). TECENTRIQ® has also been shown to have clinical activity with acceptable safety profile in patients with other solid tumors including Triple Negative Breast Cancer. The premise for combining chemotherapy with immune checkpoint inhibitors is that chemotherapy may enhance release of tumor antigens and antitumor responses to immune checkpoint inhibition. Taxanes in particular may additionally activate toll-like receptor activity and promote dendritic-cell activity. ABRAXANE® (Nanoparticle Albumin-Bound – nab Paclitaxel) was selected as a chemotherapy partner in the present study because at the time that this trial was designed, the glucocorticoid premedication that is required with solvent-based Paclitaxel (TAXOL®), had been hypothesized to affect immunotherapy activity.

IMpassion130 is an international, randomized, double-blind, placebo-controlled phase III trial in which first-line treatment with TECENTRIQ® plus ABRAXANE®, was compared with placebo plus ABRAXANE®, in patients with locally advanced or metastatic Triple Negative Breast Cancer. Patients with untreated metastatic Triple Negative Breast Cancer (N=902) were randomly assigned in a 1:1 ratio and received TECENTRIQ® 840 mg IV or placebo on days 1 and 15 and ABRAXANE® 100 mg/m2 IV on days 1, 8, and 15 of every 28-day cycle. Treatment was continued until disease progression or unacceptable toxicity. Stratification factors included presence or absence of liver metastases, use or non-use of neoadjuvant or adjuvant taxane treatment, and PD-L1 expression on tumor-infiltrating immune cells as a percentage of tumor area (less than 1% was considered PD-L1 negative versus1% or more considered PD-L1 positive) according to ImmunoHistochemical testing (IHC). Both treatment groups were well balanced. Approximately 40% of the patients were PD-L1 positive. The two Primary end points were Progression Free Survival (PFS) and Overall Survival (OS).

At a median follow up of 12.9 months, the median PFS in the intent-to-treat population was 7.2 months with TECENTRIQ® plus ABRAXANE®, as compared with 5.5 months with placebo plus ABRAXANE® (HR=0.80; P=0.002). This suggested a 20% improvement in PFS with the TECENTRIQ® combination. At the time of the first interim analysis, the median overall survival was 21.3 months in the TECENTRIQ® plus ABRAXANE® group and 17.6 months in the placebo plus ABRAXANE® group (HR for death=0.84; P=0.08). The Objective Response Rate (ORR) in the intent-to-treat population was 56% in the TECENTRIQ® and ABRAXANE® group versus 45.9% in the placebo plus ABRAXANE® group.

Among patients with PD-L1–positive tumors, the benefit was even more significant. The addition of TECENTRIQ® improved PFS by 38% (HR=0.62; P<0.001) and similar benefit was noted in the OS, with a median OS of 25 months with the TECENTRIQ® combination and 15.5 months with placebo plus ABRAXANE® (HR=0.62). Grade 3 or 4 adverse events were 48.7% in the TECENTRIQ® and ABRAXANE® and 42.2% in the placebo plus ABRAXANE® group.

It was concluded that TECENTRIQ® plus ABRAXANE® significantly prolonged Progression Free Survival among patients with metastatic Triple Negative Breast Cancer in both the intent-to-treat population and the PD-L1 positive subgroup, and could potentially change how we manage patients with Triple Negative Breast Cancer. Atezolizumab and Nab-Paclitaxel in Advanced Triple-Negative Breast Cancer. Schmid P, Adams S, Rugo HS, et al. N Engl J Med 2018; 379:2108-2121

FDA Approves KEYTRUDA® for Adjuvant Treatment of Melanoma

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SUMMARY: The FDA on February 15, 2019, approved KEYTRUDA® (Pembrolizumab) for the adjuvant treatment of patients with Melanoma with involvement of lymph node(s) following complete resection. It is estimated that in the US, approximately 96,480 new cases of Melanoma will be diagnosed in 2019 and about 7,230 patients are expected to die of the disease. The incidence of Melanoma has been on the rise for the past three decades. Surgical resection with a curative intent is the standard of care for patients with early stage Melanoma, with a 5-year survival rate of 98% for stage I disease and 90% for stage II disease. Stage III malignant Melanoma however is a heterogeneous disease, and the risk of recurrence is dependent on the number of positive nodes, as well as presence of palpable versus microscopic nodal disease. Further, patients with a metastatic focus of more than 1 mm in greatest dimension in the affected lymph node, have a significantly higher risk of recurrence or death than those with a metastasis of 1 mm or less. Patients with Stage IIIA disease have a disease-specific survival rate of 78% whereas those patients with Stage IIIB and Stage IIIC disease have disease-specific survival rates of 59% and 40% respectively. Several agents are presently approved by the FDA for the adjuvant treatment of high-risk Melanoma and they include YERVOY® (Ipilimumab), OPDIVO® (Nivolumab), TAFINLAR® (Dabrafenib) and MEKINIST® (Trametinib) for BRAF-mutant Melanoma and Interferon alfa. Unleashing-T-Cell-Function-with-Combination-Immunotherapy

KEYTRUDA® is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor and blocks its interaction with ligands PD-L1 and PD-L2. By doing so, it unleashes the tumor-specific effector T cells, and is thereby able to undo PD-1 pathway-mediated inhibition of the immune response.

The present FDA approval was based on the European Organization for Research and Treatment of Cancer (EORTC) 1325/(KEYNOTE-054) trial which is a randomized, double-blind, placebo-controlled Phase III study which involved high-risk patient population of patients with Stage III Melanoma. This study included 1019 patients with completely resected, Stage IIIA (more than 1 mm lymph node metastasis), IIIB or IIIC Melanoma. Patients were randomly assigned 1:1 to receive KEYTRUDA® 200 mg IV every three weeks (N=514) or placebo (N=505), as adjuvant therapy, for a total of 18 doses (approximately 1 year) or until disease recurrence or unacceptable toxicity. Enrolled patients required complete resection of Melanoma with negative margins and lymph node dissection. Patients with mucosal or ocular Melanoma were excluded. The Primary end points were Recurrence-Free Survival (RFS) in the overall intention-to-treat population and in the subgroup of patients with cancer that was positive for the PD-L1, as well as Safety.

At a median follow up of 15 months, KEYTRUDA® was associated with significantly longer Recurrence-Free Survival (RFS) compared to placebo in the overall intent-to-treat population, with a 1-year RFS rate of 75.4% versus 61.0% respectively (HR for recurrence or death=0.57; P<0.001). This suggested that the risk of recurrence or death in the total population was 43% lower in the KEYTRUDA® group than in the placebo group. Patients receiving KEYTRUDA® experienced fewer recurrences/deaths, 26% compared with 43% in the placebo group. The RFS benefit with KEYTRUDA® compared with placebo was observed regardless of tumor PD-L1 expression. In the subgroup of 853 patients with PD-L1-positive tumors, the 1-year RFS rate was 77.1% in the KEYTRUDA® group and 62.6% in the placebo group (HR=0.54; P<0.001). This suggested that the risk was 46% lower in the KEYTRUDA® group than in the placebo group, among patients with PD-L1-positive tumors. KEYTRUDA® was also consistently effective in patients with PD-L1-negative tumors and in those with undetermined tumor PD-L1 expression The Median RFS was 20.4 months in the placebo arm and not reached for those receiving KEYTRUDA®. The most common adverse reactions were rash, asthenia, influenza-like illness, diarrhea, pruritus, nausea, arthralgia and hypothyroidism.

It was concluded that KEYTRUDA® as adjuvant therapy for high-risk Stage III Melanoma, resulted in significantly longer Recurrence-Free Survival than placebo, with no new toxic effects identified. Adjuvant Pembrolizumab versus Placebo in Resected Stage III Melanoma. Eggermont AM, Blank CU, Mandala M, et al. N Engl J Med 2018;378:1789-1801