The FDA gave its accelerated nod to PD-1/PD-L1-targeting Bavencio (avelumab) to EMD Serono Inc., of Rockland, Mass. – the biopharmaceutical arm of Darmstadt, Germany-based Merck KGaA – for the treatment of adults and pediatric patients 12 years and older with metastatic Merkel cell carcinoma (MCC), including those who have not received prior chemotherapy. It's the first FDA-approved treatment for metastatic MCC, a rare, aggressive skin cancer.

According to the National Cancer Institute, about 1,600 people in the U.S. are diagnosed with MCC every year. While most show up with localized tumors that can be treated with surgical resection, about half of all patients will have a recurrence, and more than 30 percent will eventually develop metastatic disease.

U.S. regulators' go-ahead was based on data from a single-arm trial of 88 patients with metastatic MCC who had been previously been treated with at least one prior chemo regimen. The trial measured the percentage of patients whose tumors shrunk completely or partially (overall response rate) and, for those with a response, the length of time the tumor was controlled. Of the total, 33 percent had their tumors reduced, and the benefit lasted for more than six months in 86 percent of responding patients and more than 12 months in 45 percent of responding patients.

Merck and Pfizer Inc., of New York, are trying the compound in other tumor types, too. Last July, they began a phase III registration study to test avelumab in combination with or as follow-on treatment to platinum-based chemo in patients with metastatic, previously untreated epithelial ovarian cancer. Called Javelin Ovarian 100, the open-label study is designed to evaluate the potential superiority of avelumab combined with carboplatin/paclitaxel vs. platinum-based chemo alone, as assessed by progression-free survival. The 950 stage III-IV patients expected to be enrolled will be randomized 1:1:1 to receive concurrent avelumab and chemo, avelumab following chemo, or chemo alone. (See BioWorld Today, July 7, 2016.)

The Javelin experiment is the first phase III to test adding an immunotherapy to standard of care in first-line treatment for metastatic ovarian tumor. Merck and Pfizer struck their broad, $2.85 billion deal in November 2014. Avelumab was discovered by Merck.

Credit Suisse analyst Vamil Divan noted in a research report earlier this month that Pfizer, for its part, "is clearly making a strong push to catch up to competitors in the [immuno-oncology] space" and predicted that avelumab would win the MCC approval by mid-year, but "recently formalized changes to the Javelin lung study will prevent the drug's entry into the lucrative lung cancer indication for at least two more years. The aggressive steps [Pfizer] is taking with various combination approaches are commendable, but those will also take some time before they are at a point where we can assign them significant value."