Merck scores 'breakthrough' status from FDA for immunotherapy against melanoma

Merck ($MRK) has a shot at a speedy development path for lambrolizumab. The FDA has pinned a "Breakthrough Therapy" tag on the experimental antibody drug for advanced melanoma, based on Phase Ib data that showed significant early signs of antitumor activity in some patients with aggressive cases of the deadly skin cancer.

Often linked to too much exposure to ultraviolet rays, melanoma is expected crop up in 76,690 new cases and kill 9,480 patients in the U.S. in 2013, according to data from the National Cancer Institute.

The breakthrough recognition pushes lambrolizumab (codenamed MK-3475) into the spotlight, just where Merck wanted the antibody when the company requested that designation from U.S. regulators last year. In bestowing breakthrough status to a drug, the FDA acknowledges that the therapy has shown early evidence of significant benefits over existing therapies for life-threatening illnesses. However, the FDA only began selecting programs for the designation this year, and it's unclear how exactly the agency will handle reviews of drugs with the coveted status.

Yet the agency places the breakthrough program among others intended to bring therapies to patients in need earlier. And industry watchers have regarded the status as an endorsement of sorts for previous breakthrough designees such as Pfizer's ($PFE) breast cancer contender palbociclib, Johnson & Johnson ($JNJ) and Pharmacyclics' ($PCYC) candidate ibrutinib for blood cancers, Vertex Pharmaceuticals' ($VRTX) VX-809 and Kalydeco for cystic fibrosis, and Novartis' ($NVS) LDK378 for lung cancer.

"We are pleased that the FDA has designated lambrolizumab a Breakthrough Therapy for patients with advanced melanoma," said Dr. Gary Gilliland, senior vice president and oncology franchise head, Merck Research Laboratories, in a statement. "The FDA's decision to place lambrolizumab in a category that may enable expedited development and review is an important milestone for Merck as we advance ongoing programs in multiple cancer indications."

Merck is recruiting patients for a randomized Phase II trial of lambrolizumab, comparing two different doses of the drug and chemotherapy in advanced melanoma. In November, the U.S. drug giant reported that 51% of 85 patients in a Phase Ib study showed an objective antitumor response and 9% had a complete response at or after 12 weeks. It also showed antitumor activity in 11, or 41%, of patients who had received the gold-standard advanced melanoma med Yervoy from Bristol-Myers Squibb ($BMY).

The breakthrough status follows a letdown last year for Merck's oncology pipeline, which was hit with an FDA rejection on the sarcoma drug ridaforolimus. It was one of the R&D setbacks leading up to Merck CEO Kenneth Frazier's move earlier this year to bring in ex-Amgen ($AMGN) R&D boss Roger Perlmutter to head research at the drug giant and revive the pipeline.

Lambrolizumab, which Merck has begun to study in lung cancer and other tumors, targets a "molecular camouflage" receptor called PD-1 that tricks the immune system into treating cancer cells as normal ones to evade the immune attacks, Merck spokeswoman Caroline Lappetito told FierceBiotech in an interview. By targeting PD-1, lambrolizumab could restore the ability of immune cells to battle cancer.

- here's Merck's release
- and an item from Dow Jones Newswires
- find Reuters' article