RAHWAY, NJ. USA I December 16, 2024 I Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced the discontinuation of the clinical development programs for vibostolimab, an anti-TIGIT antibody, and favezelimab, an anti-LAG-3 antibody. Vibostolimab is being evaluated as an investigational fixed-dose combination with pembrolizumab (KEYTRUDA®) in the KeyVibe program. Favezelimab is being evaluated as an investigational fixed-dose combination with pembrolizumab in the KEYFORM program.
Merck is discontinuing the Phase 3 KeyVibe-003 and KeyVibe-007 trials, which are evaluating the fixed-dose combination of vibostolimab and pembrolizumab in certain patients with non-small cell lung cancer (NSCLC), based on the recommendation of an independent Data Monitoring Committee (DMC). In a pre-planned analysis, both trials met the pre-specified futility criteria for the primary endpoint of overall survival. In these studies, the safety profile of vibostolimab/pembrolizumab was consistent with that observed for vibostolimab and pembrolizumab in previously reported studies, with no new safety signals identified. As expected with dual checkpoint inhibitor therapy, more immune-related adverse events were observed with the fixed-dose combination than with pembrolizumab. Considering the totality of data from the Phase 3 KeyVibe studies, including the efficacy outcomes from KeyVibe-003 and KeyVibe-007, the company has decided to discontinue the Phase 3 KeyVibe-006 trial and other vibostolimab studies.
Separately, Merck has decided to end the favezelimab clinical development program, and will stop enrollment in the Phase 3 KEYFORM-008 trial evaluating the fixed-dose combination of favezelimab and pembrolizumab in patients with relapsed or refractory classical Hodgkin lymphoma (cHL) whose disease has progressed following prior anti-PD-1 therapy. Patients currently in this trial may continue on therapy until study completion. KEYFORM-008 is the only Phase 3 study in the KEYFORM clinical development program for which results are not available. The company has made this decision after a thorough evaluation of data from the favezelimab clinical program and will prioritize the development of other candidates in its comprehensive and diversified oncology pipeline. This decision is not based on any concerns about the safety of this fixed-dose combination.
Merck is informing study investigators for these clinical trials and advises patients to speak to their study team and physician regarding next steps and treatment options. Data analyses for the Phase 3 trials are ongoing, and the results will be shared with the scientific community.
“Following a careful analysis of the data, the decision has been made to discontinue development of these candidates to prioritize other ongoing programs. We are grateful to all the patients, caregivers and investigators for their many contributions that made these studies possible,” said Dr. Marjorie Green, senior vice president and head of oncology, global clinical development, Merck Research Laboratories. “We continue to pursue the most promising science with a focus on agents with the greatest potential to improve outcomes for more patients with cancer.”
About KeyVibe-003
KeyVibe-003 is a randomized, double-blind Phase 3 trial (ClinicalTrials.gov, NCT04738487) evaluating the fixed-dose combination of vibostolimab and pembrolizumab (MK-7684A) versus pembrolizumab monotherapy, as a first-line treatment for patients with PD-L1 positive metastatic NSCLC. The primary endpoint is overall survival (OS) in participants with PD-L1 TPS ≥50%. Secondary endpoints include OS in participants with PD-L1 TPS ≥1% and TPS 1-49%, progression-free survival (PFS), overall response rate (ORR), duration of response (DOR), safety and quality of life. The trial enrolled 1,264 patients who were randomized (1:1) to receive:
- Vibostolimab/pembrolizumab fixed-dose combination (pembrolizumab 200 mg and vibostolimab 200 mg intravenously [IV] every three weeks [Q3W] for up to 35 administrations); or
- Pembrolizumab (200 mg IV Q3W for up to 35 administrations)
About KeyVibe-007
KeyVibe-007 is a randomized, double-blind Phase 3 trial (ClinicalTrials.gov, NCT05226598) evaluating the fixed-dose combination of vibostolimab and pembrolizumab with chemotherapy in treatment-naïve patients with metastatic NSCLC. The primary endpoint is OS in participants with PD-L1 TPS ≥1%. Secondary endpoints include OS in all participants, PFS, ORR and DOR in TPS ≥ 1% and all participants, safety and patient reported outcomes. The trial enrolled 739 patients who were randomized (1:1) to receive:
- Vibostolimab/pembrolizumab fixed-dose combination (pembrolizumab 200mg and vibostolimab 200 mg IV) plus platinum doublet chemotherapy (Q3W for 4 cycles); then vibostolimab/pembrolizumab (200mg/200mg IV) for up to 31 cycles (plus pemetrexed 500mg/m2 Q3W maintenance for nonsquamous histology)
- Pembrolizumab (200 mg IV) plus platinum doublet chemotherapy (Q3W for 4 cycles); then pembrolizumab (200mg IV) for up to 31 cycles (plus pemetrexed 500mg/m2 Q3W maintenance for nonsquamous histology)
About KeyVibe-006
KeyVibe-006 is a randomized, open-label Phase 3 trial (ClincialTrials.gov, NCT05298423) evaluating the fixed-dose combination of vibostolimab and pembrolizumab with concurrent chemoradiotherapy followed by vibostolimab and pembrolizumab versus concurrent chemoradiotherapy followed by durvalumab in patients with stage III NSCLC. The primary endpoints are PFS and OS for all participants and for participants with TPS ≥ 1%. The secondary endpoints are ORR, DOR, safety and patient reported outcomes. The trial enrolled approximately 580 patients who were randomized (1:1) to receive:
- Vibostolimab/pembrolizumab (200mg/200mg IV) plus platinum doublet (1 cycle); then platinum doublet plus vibostolimab/pembrolizumab (2 cycles) plus thoracic radiotherapy; then vibostolimab/pembrolizumab (200mg/200mg IV Q3W for 17 cycles); or
- Platinum doublet (1 cycle); then platinum doublet (2 cycles) plus thoracic radiotherapy; then durvalumab (10 mg/kg Q2W for 26 cycles)
About KEYFORM-008
KEYFORM-008is a randomized, open-label Phase 3 trial (ClinicalTrials.gov, NCT05508867) evaluating the fixed-dose combination of favezelimab and pembrolizumab (MK-4280A) versus physician’s choice chemotherapy for the treatment of patients with PD-1 relapsed or refractory classical Hodgkin lymphoma. The primary endpoint is PFS per Lugano Response Criteria as assessed by Blinded Independent Central Review (BICR). The secondary endpoints are OS, ORR, DOR and safety. The trial enrolled 169 patients who were randomized (1:1) to receive:
- Favezelimab/pembrolizumab (800 mg/200 mg IV on day 1, then Q3W for up to 35 infusions); or
- Physician’s choice of either bendamustine (between 90-120 mg/m2 IV on day 1 and day 2 of either a 3- or 4-week cycle for up to 6 cycles); or gemcitabine (between 800-1,200 mg/m2 IV on day 1 and day 8 of a Q3W cycle for up to 6 cycles)
About vibostolimab
Vibostolimab (MK-7684) is an investigational humanized anti-TIGIT antibody discovered and developed by Merck. Vibostolimab restores antitumor activity by blocking the TIGIT receptor from binding to its ligands (CD112 and CD155), thereby activating T lymphocytes that help destroy tumor cells.
About favezelimab
Favezelimab (MK-4280) is an investigational anti-lymphocyte activation gene-3 (LAG-3) antibody. LAG-3 is a cell surface immunomodulatory receptor expressed on various immune cells that down-regulates T cell proliferation and activation. Favezelimab aims to restore T cell effector function by preventing LAG-3 from binding to its primary ligand, major histocompatibility complex (MHC) class II molecules.
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.
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.
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.
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.
Malignant Pleural Mesothelioma
KEYTRUDA, in combination with pemetrexed and platinum chemotherapy, is indicated for the first-line treatment of adult patients with unresectable advanced or metastatic malignant pleural mesothelioma (MPM).
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.
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 Cancer
KEYTRUDA, in combination with enfortumab vedotin, is indicated for the treatment of adult patients with locally advanced or metastatic urothelial cancer.
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 adults with locally advanced unresectable or metastatic HER2-positive gastric or gastroesophageal junction (GEJ) adenocarcinoma whose tumors express PD-L1 (CPS ≥1) as determined by an FDA-approved test.
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.
KEYTRUDA, in combination with fluoropyrimidine- and platinum-containing chemotherapy, is indicated for the first-line treatment of adults with locally advanced unresectable or metastatic HER2-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma.
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 chemoradiotherapy (CRT), is indicated for the treatment of patients with FIGO 2014 Stage III-IVA 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) secondary to hepatitis B who have received prior systemic therapy other than a PD-1/PD-L1-containing regimen.
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 cancer (BTC).
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, in combination with carboplatin and paclitaxel, followed by KEYTRUDA as a single agent, is indicated for the treatment of adult patients with primary advanced or recurrent endometrial carcinoma.
KEYTRUDA, as a single agent, is indicated for the treatment of adult 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.
Merck’s focus on cancer
Every day, we follow the science as we work to discover innovations that can help patients, no matter what stage of cancer they have. As a leading oncology company, we are pursuing research where scientific opportunity and medical need converge, underpinned by our diverse pipeline of more than 25 novel mechanisms. With one of the largest clinical development programs across more than 30 tumor types, we strive to advance breakthrough science that will shape the future of oncology. By addressing barriers to clinical trial participation, screening and treatment, we work with urgency to reduce disparities and help ensure patients have access to high-quality cancer care. Our unwavering commitment is what will bring us closer to our goal of bringing life to more patients with cancer. For more information, visit https://www.merck.com/research/oncology.
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 X (formerly Twitter), Facebook, Instagram, YouTube and LinkedIn.
SOURCE: Merck
