Approval based on results from the Phase 3 KEYNOTE-966 trial, which demonstrated significant overall survival benefit in these patients versus chemotherapy alone

Approval marks sixth gastrointestinal cancer indication for KEYTRUDA-based regimens in the US

RAHWAY, NJ, USA I November 01, 2023 I Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced that the U.S. Food and Drug Administration (FDA) has approved KEYTRUDA, Merck’s anti-PD-1 therapy, in combination with gemcitabine and cisplatin, for the treatment of patients with locally advanced unresectable or metastatic biliary tract cancer (BTC). The approval was based on results from the Phase 3 KEYNOTE-966 trial, in which KEYTRUDA plus chemotherapy demonstrated a statistically significant improvement in the study’s primary endpoint of overall survival (OS), reducing the risk of death by 17% (HR=0.83 [95% CI, 0.72-0.95]; one-sided p=0.0034) compared to chemotherapy alone at the trial’s pre-specified final analysis for OS. Median OS was 12.7 months (95% CI, 11.5-13.6) for KEYTRUDA plus chemotherapy versus 10.9 months (95% CI, 9.9-11.6) for chemotherapy alone. This approval marks the sixth indication for KEYTRUDA in gastrointestinal cancers.

Immune-mediated adverse reactions, which may be severe or fatal, can occur in any organ system or tissue and can affect more than one body system simultaneously. Immune-mediated adverse reactions can occur at any time during or after treatment with KEYTRUDA, including pneumonitis, colitis, hepatitis, endocrinopathies, nephritis, dermatologic reactions, solid organ transplant rejection, and complications of allogeneic hematopoietic stem cell transplantation. Important immune-mediated adverse reactions listed here may not include all possible severe and fatal immune-mediated adverse reactions. Early identification and management of immune-mediated adverse reactions are essential to ensure safe use of KEYTRUDA. Based on the severity of the adverse reaction, KEYTRUDA should be withheld or permanently discontinued and corticosteroids administered if appropriate. KEYTRUDA can also cause severe or life-threatening infusion-related reactions. Based on its mechanism of action, KEYTRUDA can cause fetal harm when administered to a pregnant woman. For more information, see “Selected Important Safety Information” below.

“Cancers of the biliary tract can be highly aggressive tumors, underscoring the need for additional treatment options for the growing number of patients facing this challenging disease,” said Dr. Robin Kate Kelley, professor of clinical medicine in the division of hematology/oncology, University of California, San Francisco. “Today’s approval of pembrolizumab in combination with chemotherapy offers patients with locally advanced unresectable or metastatic biliary tract cancer a new immunotherapy regimen that has demonstrated the potential to help these patients live longer.”

“Many patients with biliary tract cancer are diagnosed with locally advanced or metastatic disease, at which point they are not eligible for surgery and face poor survival outcomes with limited treatment options,” said Dr. Marjorie Green, senior vice president and head of late-stage oncology, global clinical development, Merck Research Laboratories. “With this approval, Merck is proud to offer a new treatment option to certain patients with locally advanced unresectable or metastatic biliary tract cancer, and their healthcare providers, that has shown an overall survival benefit compared to chemotherapy alone.”

Study design and additional data supporting the approval

KEYNOTE-966 is a multicenter, double-blind, randomized, placebo-controlled Phase 3 trial (ClinicalTrials.gov, NCT04003636) evaluating KEYTRUDA in combination with gemcitabine and cisplatin for the treatment of patients with locally advanced unresectable or metastatic BTC who had not received prior systemic therapy in the advanced disease setting. The trial enrolled 1,069 patients.

Patients were randomized (1:1) to KEYTRUDA (200 mg) on Day 1 plus gemcitabine (1,000 mg/m2) and cisplatin (25 mg/m2) on Day 1 and Day 8 every three weeks (n=533), or placebo on Day 1 plus gemcitabine (1,000 mg/m2) and cisplatin (25 mg/m2) on Day 1 and Day 8 every three weeks (n=536). Study medications were administered via intravenous infusion. Treatment continued until unacceptable toxicity or disease progression. For KEYTRUDA, treatment continued for a maximum of 35 cycles (or approximately 24 months). For gemcitabine, treatment could be continued beyond eight cycles, while for cisplatin, treatment could be administered for a maximum of eight cycles. Administration of KEYTRUDA with chemotherapy was permitted beyond RECIST-defined disease progression if the patient was clinically stable and considered by the investigator to be deriving clinical benefit. Assessment of tumor status was performed at baseline and then every six weeks through 54 weeks, followed by every 12 weeks thereafter.

The major efficacy outcome measure was OS. Additional efficacy outcome measures were progression-free survival (PFS), objective response rate (ORR) and duration of response (DOR) as assessed by blinded independent central review (BICR) according to RECIST v1.1, modified to follow a maximum of 10 target lesions and a maximum of five target lesions per organ.

At the trial’s pre-specified final analysis for PFS and ORR, KEYTRUDA plus chemotherapy reduced the risk of disease progression or death by 14% (HR=0.86 [95% CI, 0.75-1.00]) compared to chemotherapy alone. Median PFS was 6.5 months (95% CI, 5.7-6.9) for KEYTRUDA plus chemotherapy versus 5.6 months (95% CI, 5.1-6.6) for chemotherapy alone; however, this result did not reach statistical significance at this analysis. The ORR for KEYTRUDA plus chemotherapy was 29% (95% CI, 25-33), with a complete response (CR) rate of 2.1% (n=11) and a partial response (PR) rate of 27% (n=142), and the ORR for chemotherapy alone was 29% (95% CI, 25-33), with a CR rate of 1.3% (n=7) and a PR rate of 27% (n=146). At the trial’s pre-specified final analysis for OS, median DOR was 8.3 months (95% CI, 6.9-10.2) for KEYTRUDA plus chemotherapy (n=156) versus 6.8 months (95% CI, 5.7-7.1) for chemotherapy alone (n=152).

The median duration of exposure to KEYTRUDA was six months (range, 1 day to 28 months). KEYTRUDA was discontinued due to adverse reactions in 15% of patients. The most common adverse reaction resulting in permanent discontinuation of KEYTRUDA (≥1%) was pneumonitis (1.3%). Adverse reactions leading to interruption of KEYTRUDA occurred in 55% of patients; the most common adverse reactions or laboratory abnormalities leading to interruption of KEYTRUDA (≥2%) were decreased neutrophil count (18%), decreased platelet count (10%), anemia (6%), decreased white blood count (4%), pyrexia (3.8%), fatigue (3.0%), cholangitis (2.8%), increased alanine aminotransferase (ALT) (2.6%), increased aspartate aminotransferase (AST) (2.5%) and biliary obstruction (2.3%).

In the KEYTRUDA plus chemotherapy versus placebo plus chemotherapy arms, there was a difference of ≥5% incidence in adverse reactions between patients who received KEYTRUDA versus placebo for pyrexia (26% vs. 20%), rash (21% vs. 13%), pruritus (15% vs. 10%) and hypothyroidism (9% vs. 2.6%). There were no clinically meaningful differences in incidence of Grade 3-4 toxicity between arms.

There was a difference of ≥5% incidence in laboratory abnormalities between patients who received KEYTRUDA plus chemotherapy versus placebo plus chemotherapy for decreased lymphocytes (69% vs. 61%). There were no clinically meaningful differences in incidence of Grade 3-4 toxicity between arms.

About biliary tract cancer

Biliary tract cancer (BTC) is a group of rare and highly aggressive cancers in the liver, gallbladder and bile ducts. Biliary tract cancer is the second most common type of primary liver cancer after hepatocellular carcinoma (HCC), accounting for approximately 15% of all liver cancers. 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 and 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 relative survival rate of 2-3% for those diagnosed with advanced disease and 9-11% 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.

Biliary Tract Cancer

KEYTRUDA, in combination with gemcitabine and cisplatin, is indicated for the treatment of patients with locally advanced unresectable or metastatic biliary tract carcinoma (BTC).

Melanoma

KEYTRUDA is indicated for the treatment of patients with unresectable or metastatic melanoma.

KEYTRUDA is indicated for the adjuvant treatment of adult and pediatric (12 years and older) patients with stage IIB, IIC, or III melanoma following complete resection.

Non-Small Cell Lung Cancer

KEYTRUDA, in combination with pemetrexed and platinum chemotherapy, is indicated for the first-line treatment of patients with metastatic nonsquamous non-small cell lung cancer (NSCLC), with no EGFR or ALK genomic tumor aberrations.

KEYTRUDA, in combination with carboplatin and either paclitaxel or paclitaxel protein-bound, is indicated for the first-line treatment of patients with metastatic squamous NSCLC.

KEYTRUDA, as a single agent, is indicated for the first-line treatment of patients with NSCLC expressing PD-L1 [tumor proportion score (TPS) ≥1%] as determined by an FDA-approved test, with no EGFR or ALK genomic tumor aberrations, and is:

  • stage III where patients are not candidates for surgical resection or definitive chemoradiation, or
  • metastatic.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with metastatic NSCLC whose tumors express PD-L1 (TPS ≥1%) as determined by an FDA-approved test, with disease progression on or after platinum-containing chemotherapy. Patients with EGFR or ALK genomic tumor aberrations should have disease progression on FDA-approved therapy for these aberrations prior to receiving KEYTRUDA.

KEYTRUDA is indicated for the treatment of patients with resectable (tumors ≥4 cm or node positive) NSCLC in combination with platinum-containing chemotherapy as neoadjuvant treatment, and then continued as a single agent as adjuvant treatment after surgery.

KEYTRUDA, as a single agent, is indicated as adjuvant treatment following resection and platinum-based chemotherapy for adult patients with Stage IB (T2a ≥4 cm), II, or IIIA NSCLC.

Head and Neck Squamous Cell Cancer

KEYTRUDA, in combination with platinum and fluorouracil (FU), is indicated for the first-line treatment of patients with metastatic or with unresectable, recurrent head and neck squamous cell carcinoma (HNSCC).

KEYTRUDA, as a single agent, is indicated for the first-line treatment of patients with metastatic or with unresectable, recurrent HNSCC whose tumors express PD-L1 [Combined Positive Score (CPS) ≥1] as determined by an FDA-approved test.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with recurrent or metastatic HNSCC with disease progression on or after platinum-containing chemotherapy.

Classical Hodgkin Lymphoma

KEYTRUDA is indicated for the treatment of adult patients with relapsed or refractory classical Hodgkin lymphoma (cHL).

KEYTRUDA is indicated for the treatment of pediatric patients with refractory cHL, or cHL that has relapsed after 2 or more lines of therapy.

Primary Mediastinal Large B-Cell Lymphoma

KEYTRUDA is indicated for the treatment of adult and pediatric patients with refractory primary mediastinal large B-cell lymphoma (PMBCL), or who have relapsed after 2 or more prior lines of therapy.

KEYTRUDA is not recommended for treatment of patients with PMBCL who require urgent cytoreductive therapy.

Urothelial Carcinoma

KEYTRUDA, in combination with enfortumab vedotin, is indicated for the treatment of adult patients with locally advanced or metastatic urothelial carcinoma who are not eligible for cisplatin-containing chemotherapy.

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.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with locally advanced or metastatic urothelial carcinoma:

  • who are not eligible for any platinum-containing chemotherapy, or
  • who have disease progression during or following platinum-containing chemotherapy or within 12 months of neoadjuvant or adjuvant treatment with platinum-containing chemotherapy.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with Bacillus Calmette-Guerin (BCG)-unresponsive, high-risk, non-muscle invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) with or without papillary tumors who are ineligible for or have elected not to undergo cystectomy.

Microsatellite Instability-High or Mismatch Repair Deficient Cancer

KEYTRUDA is indicated for the treatment of adult and pediatric patients with unresectable or metastatic microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) solid tumors, as determined by an FDA-approved test, that have progressed following prior treatment and who have no satisfactory alternative treatment options.

Microsatellite Instability-High or Mismatch Repair Deficient Colorectal Cancer

KEYTRUDA is indicated for the treatment of patients with unresectable or metastatic MSI-H or dMMR colorectal cancer (CRC) as determined by an FDA-approved test.

Gastric Cancer

KEYTRUDA, in combination with trastuzumab, fluoropyrimidine- and platinum-containing chemotherapy, is indicated for the first-line treatment of patients with locally advanced unresectable or metastatic HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma.

This indication is approved under accelerated approval based on tumor response rate and durability of response. Continued approval of this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials.

Esophageal Cancer

KEYTRUDA is indicated for the treatment of patients with locally advanced or metastatic esophageal or gastroesophageal junction (GEJ) (tumors with epicenter 1 to 5 centimeters above the GEJ) carcinoma that is not amenable to surgical resection or definitive chemoradiation either:

  • in combination with platinum- and fluoropyrimidine-based chemotherapy, or
  • as a single agent after one or more prior lines of systemic therapy for patients with tumors of squamous cell histology that express PD-L1 (CPS ≥10) as determined by an FDA-approved test.

Cervical Cancer

KEYTRUDA, in combination with chemotherapy, with or without bevacizumab, is indicated for the treatment of patients with persistent, recurrent, or metastatic cervical cancer whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test.

KEYTRUDA, as a single agent, is indicated for the treatment of patients with recurrent or metastatic cervical cancer with disease progression on or after chemotherapy whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test.

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.

Merkel Cell Carcinoma

KEYTRUDA is indicated for the treatment of adult and pediatric patients with recurrent locally advanced or metastatic Merkel cell carcinoma (MCC).

Renal Cell Carcinoma

KEYTRUDA, in combination with axitinib, is indicated for the first-line treatment of adult patients with advanced renal cell carcinoma (RCC).

KEYTRUDA is indicated for the adjuvant treatment of patients with RCC at intermediate-high or high risk of recurrence following nephrectomy, or following nephrectomy and resection of metastatic lesions.

Endometrial Carcinoma

KEYTRUDA, as a single agent, is indicated for the treatment of patients with advanced endometrial carcinoma that is MSI-H or dMMR, as determined by an FDA-approved test, who have disease progression following prior systemic therapy in any setting and are not candidates for curative surgery or radiation.

Tumor Mutational Burden-High Cancer

KEYTRUDA is indicated for the treatment of adult and pediatric patients with unresectable or metastatic tumor mutational burden-high (TMB-H) [≥10 mutations/megabase (mut/Mb)] solid tumors, as determined by an FDA-approved test, that have progressed following prior treatment and who have no satisfactory alternative treatment options.

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.

The safety and effectiveness of KEYTRUDA in pediatric patients with TMB-H central nervous system cancers have not been established.

Cutaneous Squamous Cell Carcinoma

KEYTRUDA is indicated for the treatment of patients with recurrent or metastatic cutaneous squamous cell carcinoma (cSCC) or locally advanced cSCC that is not curable by surgery or radiation.

Triple-Negative Breast Cancer

KEYTRUDA is indicated for the treatment of patients with high-risk early-stage triple-negative breast cancer (TNBC) in combination with chemotherapy as neoadjuvant treatment, and then continued as a single agent as adjuvant treatment after surgery.

KEYTRUDA, in combination with chemotherapy, is indicated for the treatment of patients with locally recurrent unresectable or metastatic TNBC whose tumors express PD-L1 (CPS ≥10) as determined by an FDA-approved test.

About the Merck Access Program for KEYTRUDA

At Merck, we are committed to supporting accessibility to our cancer medicines. Merck provides multiple programs to help appropriate patients who are prescribed KEYTRUDA have access to our anti-PD-1 therapy. The Merck Access Program provides reimbursement support for patients receiving KEYTRUDA, including information to help with out-of-pocket costs and co-pay assistance for eligible patients. More information is available by calling 855-257-3932 or visiting www.merckaccessprogram-keytruda.com.

About Merck’s Patient Support Program for KEYTRUDA

Merck is committed to helping provide patients and their caregivers support throughout their treatment with KEYTRUDA. The KEY+YOU Patient Support Program provides a range of resources and support. For further information and to sign up, eligible patients may call 85-KEYTRUDA (855-398-7832) or visit www.keytruda.com.

Merck’s focus on cancer

Our goal is to translate breakthrough science into innovative oncology medicines to help people with cancer worldwide. At Merck, the potential to bring new hope to people with cancer drives our purpose and supporting accessibility to our cancer medicines is our commitment. As part of our focus on cancer, Merck is committed to exploring the potential of immuno-oncology with one of the largest development programs in the industry across more than 30 tumor types. We also continue to strengthen our portfolio through strategic acquisitions and are prioritizing the development of several promising oncology candidates with the potential to improve the treatment of advanced cancers. For more information about our oncology clinical trials, visit www.merck.com/clinicaltrials.

About Merck

At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy future for all people and communities. For more information, visit www.merck.com and connect with us on Twitter, Facebook, Instagram, YouTube and LinkedIn.

SOURCE: Merck