First Presentation of OS Data From Phase 3 KEYNOTE-394 Trial at ASCO GI 2022

KEYNOTE-394 Is One of Seven Clinical Trials in Merck’s Global Development Program in HCC

KENILWORTH, NJ, USA I January 18, 2022 I Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced the final results from the Phase 3 KEYNOTE-394 trial investigating KEYTRUDA, Merck’s anti-PD-1 therapy, plus best supportive care (BSC) in patients in Asia with advanced hepatocellular carcinoma (HCC) previously treated with sorafenib. KEYNOTE-394 is the first trial with an anti-PD-1/L1 as a second-line monotherapy treatment to show an improvement in overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) compared to placebo plus BSC for these patients. These data add to the body of evidence relating to the use of KEYTRUDA as a monotherapy in second-line HCC post sorafenib.

KEYTRUDA plus BSC demonstrated a statistically significant and clinically meaningful improvement in the primary endpoint of OS, reducing the risk of death by 21% (HR=0.79 [95% CI, 0.63-0.99]; p=0.0180) compared to placebo plus BSC for patients with previously treated advanced HCC. For patients treated with KEYTRUDA plus BSC, median OS was 14.6 months (95% CI, 12.6-18.0) compared to 13.0 months (95% CI, 10.5-15.1) for patients treated with placebo plus BSC. The percentage of patients who were alive at two years was 34.3% for KEYTRUDA plus BSC compared to 24.9% for placebo plus BSC. These data will be presented at the 2022 American Society of Clinical Oncology Gastrointestinal Cancers (ASCO GI) Symposium (Abstract #352788) on Friday, Jan. 21 at 10:15 a.m. ET.

“Hepatocellular carcinoma is a leading cause of cancer death across the world, and there are limited treatment options shown to extend survival for patients following treatment with sorafenib,” said Dr. Shukui Qin, director, Cancer Center of Jinling Hospital, and professor, Nanjing University of Chinese Medicine. “These overall survival data are very encouraging for patients with HCC previously treated with sorafenib and show the potential of KEYTRUDA to extend the lives of these patients.”

Treatment-related adverse events (TRAEs) occurred in 66.9% of patients in the KEYTRUDA plus BSC arm and 49.7% of patients in the placebo plus BSC arm, and Grade 3-5 TRAEs occurred in 14.4% of patients in the KEYTRUDA plus BSC arm and 5.9% of patients in placebo plus BSC arm. Immune-mediated adverse events (AEs) of any grade occurred in 18.1% of patients receiving KEYTRUDA plus BSC and 10.5% of patients receiving placebo plus BSC. Grade 3-5 immune-mediated AEs occurred in 3.0% of patients receiving KEYTRUDA plus BSC. There were three deaths (due to gastrointestinal hemorrhage, autoimmune hepatitis, and soft tissue infection) in the KEYTRUDA arm related to the study intervention.

“Patients with advanced HCC still have a high unmet medical need with low survival rates, reinforcing the need for treatment options that can improve overall survival,” said Dr. Scot Ebbinghaus, vice president, clinical research, Merck Research Laboratories. “We are pleased to share these new data from KEYNOTE-394 and are committed to advancing research for patients with this difficult-to-treat cancer through our broad global program in HCC.”

In the U.S., KEYTRUDA is indicated for the treatment of patients with HCC who have been previously treated with sorafenib based on ORR and duration of response (DOR) data from KEYNOTE-224. 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. Data from KEYNOTE-394 are being discussed with global regulatory authorities and will be evaluated as a potential confirmatory study in the U.S.

Merck is dedicated to advancing research in HCC and has a global development program of seven clinical trials that have enrolled or are expected to enroll approximately 3,000 patients. In HCC, KEYTRUDA is being studied across multiple settings and lines of therapy as monotherapy and in combination with other treatments, including therapies through our collaborations.

Study Design and Additional Data From KEYNOTE-394

KEYNOTE-394 (ClinicalTrials.gov, NCT03062358) is a randomized, double-blind Phase 3 trial evaluating KEYTRUDA plus BSC versus placebo plus BSC in Asian patients with advanced HCC previously treated with sorafenib or oxaliplatin-based chemotherapy. The primary endpoint is OS. Additional endpoints include PFS, ORR, and DOR. The study enrolled 453 patients who were randomized to receive either KEYTRUDA (intravenously every three weeks for up to 35 cycles of treatment [up to approximately two years]) plus BSC (including pain management and management of other potential complications including ascites per local standards of care) or placebo plus BSC.

Additional efficacy endpoint results of the trial showed KEYTRUDA plus BSC reduced the risk of disease progression or death by 26% (HR=0.74 [95% CI, 0.60-0.92]; p=0.0032) compared to placebo plus BSC. Median PFS was 2.6 months (95% CI, 1.5-2.8) for KEYTRUDA plus BSC and 2.3 months (95% CI, 1.4-2.8) for placebo plus BSC. KEYTRUDA plus BSC showed an ORR of 12.7% (95% CI, 9.1-17.0) and a median DOR of 23.9 months (range, 2.8 to 32.0+), where placebo plus BSC showed an ORR of 1.3% (95% CI, 0.2-4.6) and a median DOR of 5.6 months (range, 3.0+ to 5.6).

About Liver Cancer and Hepatocellular Carcinoma

Liver cancer is one of the leading causes of cancer-related deaths worldwide. It is estimated there were more than 905,000 new cases of liver cancer and more than 830,000 deaths from the disease globally in 2020. In the U.S., it is estimated there will be more than 41,000 new cases of liver cancer diagnosed and more than 30,000 deaths from this disease in 2022. An estimated 75% to 90% of primary liver cancer cases are hepatocellular carcinoma (HCC). Worldwide, major factors that increase the risk of HCC are chronic hepatitis B and chronic hepatitis C, alcohol use, and metabolic syndrome.

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.

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.

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 is indicated for the treatment of patients with locally advanced or metastatic urothelial carcinoma (mUC):

  • 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.

Non-muscle Invasive Bladder Cancer

KEYTRUDA 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 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 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 MSI-H central nervous system cancers have not been established.

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).

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 for 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 (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). 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.

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.

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] 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.

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

For over 130 years, Merck, known as MSD outside the United States and Canada, has been inventing for life, bringing forward medicines and vaccines for many of the world’s most challenging diseases in pursuit of our mission to save and improve lives. We demonstrate our commitment to patients and population health by increasing access to health care through far-reaching policies, programs and partnerships. Today, Merck continues to be at the forefront of research to prevent and treat diseases that threaten people and animals – including cancer, infectious diseases such as HIV and Ebola, and emerging animal diseases – as we aspire to be the premier research-intensive biopharmaceutical company in the world. For more information, visit www.merck.com and connect with us on Twitter, Facebook, Instagram, YouTube and LinkedIn.

SOURCE: Merck