Acceptance based on results from the Phase 3 KEYNOTE-966 trial, which showed a significant overall survival benefit in these patients

RAHWAY, N.J.--(BUSINESS WIRE)-- Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced the U.S. Food and Drug Administration (FDA) has accepted for review a new supplemental Biologics License Application (sBLA) seeking approval for KEYTRUDA, Merck’s anti-PD-1 therapy, in combination with standard of care chemotherapy (gemcitabine and cisplatin) for the treatment of patients with locally advanced unresectable or metastatic biliary tract cancer (BTC). The sBLA is based on data from the KEYNOTE-966 trial, in which KEYTRUDA plus chemotherapy demonstrated a statistically significant improvement in overall survival (OS) compared to chemotherapy alone. Results from KEYNOTE-966 were presented at the American Association for Cancer Research (AACR) 2023 Annual Meeting. The FDA has set a Prescription Drug User Fee Act (PDUFA), or target action, date of February 7, 2024.

“Most biliary tract cancers go undetected until an advanced stage, at which point many patients are ineligible for surgery and have few treatment options,” said Dr. Scot Ebbinghaus, vice president, global clinical development, Merck Research Laboratories. “We look forward to working with the FDA to bring a new option to patients with advanced or unresectable biliary tract cancer that may help them live longer.”

Merck has an extensive clinical development program evaluating KEYTRUDA in gastrointestinal cancers, which includes KEYNOTE-937 in earlier-stage hepatocellular carcinoma (HCC), and in combination with LENVIMA® (lenvatinib, in collaboration with Eisai) and transarterial chemoembolization (TACE) in the LEAP-012 study. Merck is continuing to study KEYTRUDA for multiple uses in hepatobiliary, esophageal, pancreatic, colorectal and gastric cancers.

About KEYNOTE-966

KEYNOTE-966 is a randomized, double-blind Phase 3 trial (ClinicalTrials.gov, NCT04003636) evaluating KEYTRUDA in combination with gemcitabine and cisplatin compared to placebo plus gemcitabine and cisplatin for the first-line treatment of advanced or unresectable BTC. The primary endpoint is OS, and the secondary endpoints include progression-free survival, objective response rate, duration of response and safety. The trial enrolled 1,069 patients who were randomized to receive KEYTRUDA (200 mg every three weeks for up to approximately two years) plus gemcitabine and cisplatin, or placebo plus gemcitabine and cisplatin.

About biliary tract cancer

Biliary tract cancer is a group of rare and highly aggressive cancers in the gallbladder and bile ducts. Biliary tract cancer is the second most common type of primary liver cancer after HCC, accounting for approximately 15% of all liver cancers. It is estimated there are approximately 211,000 patients diagnosed with BTC and 174,000 patient deaths from the disease each year globally. In the U.S., there are about 20,000 patients diagnosed with BTC each year. Biliary tract cancer is most frequently diagnosed in patients between 50 to 70 years old, and approximately 70% of BTC patients are diagnosed at an advanced stage. Patients diagnosed with BTC face a very poor prognosis, with a five-year survival rate of 2% for those diagnosed with advanced disease and between 5% and 15% for those diagnosed across all stages.

About KEYTRUDA® (pembrolizumab) injection, 100 mg

KEYTRUDA is an anti-programmed death receptor-1 (PD-1) therapy that works by increasing the ability of the body’s immune system to help detect and fight tumor cells. KEYTRUDA is a humanized monoclonal antibody that blocks the interaction between PD-1 and its ligands, PD- L1 and PD-L2, thereby activating T lymphocytes which may affect both tumor cells and healthy cells.

Merck has the industry’s largest immuno-oncology clinical research program. There are currently more than 1,600 trials studying KEYTRUDA across a wide variety of cancers and treatment settings. The KEYTRUDA clinical program seeks to understand the role of KEYTRUDA across cancers and the factors that may predict a patient's likelihood of benefitting from treatment with KEYTRUDA, including exploring several different biomarkers.

Selected KEYTRUDA® (pembrolizumab) Indications in the U.S.

Hepatocellular Carcinoma

KEYTRUDA is indicated for the treatment of patients with hepatocellular carcinoma (HCC) who have been previously treated with sorafenib. This indication is approved under accelerated approval based on tumor response rate and durability of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials.

See additional selected KEYTRUDA indications in the U.S. after the Selected Important Safety Information.

Selected Important Safety Information for KEYTRUDA

Severe and Fatal Immune-Mediated Adverse Reactions

KEYTRUDA is a monoclonal antibody that belongs to a class of drugs that bind to either the PD-1 or the PD-L1, blocking the PD-1/PD-L1 pathway, thereby removing inhibition of the immune response, potentially breaking peripheral tolerance and inducing immune-mediated adverse reactions. Immune-mediated adverse reactions, which may be severe or fatal, can occur in any organ system or tissue, can affect more than one body system simultaneously, and can occur at any time after starting treatment or after discontinuation of treatment. Important immune-mediated adverse reactions listed here may not include all possible severe and fatal immune-mediated adverse reactions.

Monitor patients closely for symptoms and signs that may be clinical manifestations of underlying immune-mediated adverse reactions. Early identification and management are essential to ensure safe use of anti–PD-1/PD-L1 treatments. Evaluate liver enzymes, creatinine, and thyroid function at baseline and periodically during treatment. For patients with TNBC treated with KEYTRUDA in the neoadjuvant setting, monitor blood cortisol at baseline, prior to surgery, and as clinically indicated. In cases of suspected immune-mediated adverse reactions, initiate appropriate workup to exclude alternative etiologies, including infection. Institute medical management promptly, including specialty consultation as appropriate.

Withhold or permanently discontinue KEYTRUDA depending on severity of the immune-mediated adverse reaction. In general, if KEYTRUDA requires interruption or discontinuation, administer systemic corticosteroid therapy (1 to 2 mg/kg/day prednisone or equivalent) until improvement to Grade 1 or less. Upon improvement to Grade 1 or less, initiate corticosteroid taper and continue to taper over at least 1 month. Consider administration of other systemic immunosuppressants in patients whose adverse reactions are not controlled with corticosteroid therapy.

Immune-Mediated Pneumonitis

KEYTRUDA can cause immune-mediated pneumonitis. The incidence is higher in patients who have received prior thoracic radiation. Immune-mediated pneumonitis occurred in 3.4% (94/2799) of patients receiving KEYTRUDA, including fatal (0.1%), Grade 4 (0.3%), Grade 3 (0.9%), and Grade 2 (1.3%) reactions. Systemic corticosteroids were required in 67% (63/94) of patients. Pneumonitis led to permanent discontinuation of KEYTRUDA in 1.3% (36) and withholding in 0.9% (26) of patients. All patients who were withheld reinitiated KEYTRUDA after symptom improvement; of these, 23% had recurrence. Pneumonitis resolved in 59% of the 94 patients.

Pneumonitis occurred in 8% (31/389) of adult patients with cHL receiving KEYTRUDA as a single agent, including Grades 3-4 in 2.3% of patients. Patients received high-dose corticosteroids for a median duration of 10 days (range: 2 days to 53 months). Pneumonitis rates were similar in patients with and without prior thoracic radiation. Pneumonitis led to discontinuation of KEYTRUDA in 5.4% (21) of patients. Of the patients who developed pneumonitis, 42% interrupted KEYTRUDA, 68% discontinued KEYTRUDA, and 77% had resolution.

Pneumonitis occurred in 7% (41/580) of adult patients with resected NSCLC who received KEYTRUDA as a single agent for adjuvant treatment of NSCLC, including fatal (0.2%), Grade 4 (0.3%), and Grade 3 (1%) adverse reactions. Patients received high-dose corticosteroids for a median duration of 10 days (range: 1 day to 2.3 months). Pneumonitis led to discontinuation of KEYTRUDA in 26 (4.5%) of patients. Of the patients who developed pneumonitis, 54% interrupted KEYTRUDA, 63% discontinued KEYTRUDA, and 71% had resolution.

Immune-Mediated Colitis

KEYTRUDA can cause immune-mediated colitis, which may present with diarrhea. Cytomegalovirus infection/reactivation has been reported in patients with corticosteroid-refractory immune-mediated colitis. In cases of corticosteroid-refractory colitis, consider repeating infectious workup to exclude alternative etiologies. Immune-mediated colitis occurred in 1.7% (48/2799) of patients receiving KEYTRUDA, including Grade 4 (