Keytruda Flounders Lung Cancer Trial but Scores Key Win for Bladder Cancer

By Rajaneesh K. Gopinath, Ph.D.

A rare stumble in a late-stage, small cell lung cancer trial followed by a key approval for the treatment of non-muscle invasive bladder cancer (NMIBC) summed up a week of mixed returns for the blockbuster anti-PD1 drug.

It was quite a roller coaster ride for Merck last week, which initially started off with the announcement of a new collaboration with Taiho and Astex and then having to break the news of Keytruda (pembrolizumab)’s failure in a phase III trial. Within the next few days, the company scored an important FDA approval for the drug to finish the week on a high. Merck reported that while Keytruda met the progression-free survival (PFS), one of the primary endpoints of the KEYNOTE-604 trial, it did not meet the other endpoint of overall survival (OS). Although there were some improvements in OS in the drug arm, it did not satisfy the statistical requirements.

Keytruda in combination with pemetrexed and platinum chemotherapy is a prescribed therapeutic for the treatment of Non-small cell lung cancer (NSCLC), the most common form of lung cancer accounting for 85% of all cases. Small cell lung cancer, on the other hand, accounts only for 10-15%.

FDA Approval

Later in the week, Merck announced Keytruda’s FDA approval as a monotherapy for the treatment of patients with non-muscle invasive bladder cancer (NMIBC). These patients are the ones who are unresponsive to the immune stimulant Bacillus Calmette-Guerin (BCG) and who are ineligible or refused a surgical removal of the urinary bladder (cystectomy). The approval is a result of the drug’s strong showing in KEYNOTE-057 (NCT02625961), a multicenter, open-label, single-arm trial involving 96 patients. The recommended dose is 200 mg every 3 weeks. Common adverse reactions included fatigue, diarrhea, rash, pruritus, musculoskeletal pain, hematuria, cough, arthralgia, nausea, constipation, urinary tract infection, peripheral edema, hypothyroidism, and nasopharyngitis.

This is just another feather in the hat for Keytruda which has been notching a number of approvals for a long list of other indications including melanoma, classical Hodgkin lymphoma, urothelial carcinoma, hepatocellular carcinoma, renal cell carcinoma among others.

“Today’s approval of Keytruda reinforces our company’s commitment to expanding existing treatment options for certain patients with high-risk, non-muscle invasive bladder cancer,” said Dr. Scot Ebbinghaus, vice president, clinical research, Merck Research Laboratories. “As the first anti-PD-1 therapy approved in this setting, KEYTRUDA will be a new clinical option for a patient population that previously had limited FDA-approved therapies available.”

Related Article: Yet Another Feather in Merck’s Crown, Keytruda Meets Endpoint in Phase 3 Trial for Triple Negative Breast Cancer

References

1. https://investors.merck.com/news/press-release-details/2020/Mercks-KEYTRUDA-pembrolizumab-in-Combination-with-Chemotherapy-Significantly-Improved-Progression-Free-Survival-Compared-to-Chemotherapy-Alone-as-First-Line-Treatment-for-Extensive-Stage-Small-Cell-Lung-Cancer/default.aspx
2. https://investors.merck.com/news/press-release-details/2020/FDA-Approves-Mercks-KEYTRUDA-pembrolizumab-for-Patients-With-BCG-Unresponsive-High-Risk-Non-Muscle-Invasive-Bladder-Cancer-With-Carcinoma-In-Situ-With-or-Without-Papillary-Tumors-Who-Are-Ineligible-for-or-Have-Elected-Not-to-Undergo-Cystectomy/default.aspx

Author

Rajaneesh K. Gopinath