Merck Drug Shows No Life-Extending Benefit in Head-and-Neck Cancer

Xconomy Boston — 

The first immunotherapy approved in the U.S. to treat head and neck cancer has failed a big test, but it’s unclear if the FDA will exercise its right to pull it from the market.

Merck (NYSE: MRK) announced late Monday that its blockbuster cancer drug pembrolizumab (Keytruda) did not meet its main goal of helping people live longer in a key trial, dubbed KEYNOTE-040. The FDA gave pembrolizumab a fast-track approval last August based on a subset of the 040 data that showed the drug was shrinking tumors. But the agency required positive results in the future, including evidence of a survival benefit over standard chemotherapy.

The approval is for patients with head and neck squamous cell carcinoma that has returned or spread to other parts of the body after treatment with chemotherapy.

The FDA approved nivolumab (Opdivo), from Merck’s top immunotherapy rival Bristol-Myers Squibb (NYSE: BMY), for the same patient population last November. Bristol’s approval was based on data that showed nivolumab improved survival by a median of 2.4 months over chemotherapy.

Merck said today that pembrolizumab’s approval for head-and-neck cancer is not in immediate danger of being revoked. “We have already discussed these data with the FDA and do not anticipate any changes to the current indication at this time,” a Merck spokeswoman told Xconomy via email.

Merck did not release data except to say that pembrolizumab did not meet its primary endpoint of overall survival. Merck also said that “no new safety signals were identified” and that the level of side effects was consistent with other pembrolizumab studies. It will discuss the data later at an unspecified medical meeting. The spokeswoman also noted that pembrolizumab was currently being studied in two other head-and-neck cancer trials; she declined to speculate whether data from those trials would factor into the drug’s continued approval.

Head-and-neck cancer, often caused by the human papillomavirus, accounts for about 15 percent of pembrolizumab sales, according to ISI Evercore analyst Umer Raffat.

Merck shares are down 57 cents, or 0.9 percent, in after-hours trading.

The news comes as the FDA’s drug approval rate has spiked in 2017. The 26 OKs so far have surpassed 2016’s total and could threaten historical high-water marks.

While accelerated approvals are fairly common, withdrawal is rare. The only case, in 2011, was the cancellation of bevacizumab (Avastin) for use in breast cancer.
The agency has yet to rescind the 2016 conditional approval of Roche’s atezolizumab (Teqcentriq) in bladder cancer, which failed to show a survival benefit in a 931-patient study this May.

Head and neck cancer kills more than 9,000 Americans a year, about the same as skin cancer. The top U.S. cancer killers are lung, colon, breast, and prostate cancers, according to the Centers for Disease Control.

Pembrolizumab is also approved for certain types of skin cancer, bladder cancer, lung cancer, lymphoma, and for patients with tumors that have a specific genetic fingerprint—the first time a drug was approved for a cancer’s genetic profile instead of the cancer’s organ or tissue of origin.

Image “Human Papillomavirus (HPV) in Head and Neck Cancer” by Ernesto del Aguila III/NHGRI via Creative Commons 2.0 license.