Lambrolizumab Receives ‘Breakthrough Therapy’ Designation for Melanoma
Antibody therapy prevents cancer cells from ‘hiding in plain sight’ (Apr. 24)
The FDA has designated lambrolizumab (MK-3475, Merck) as a “breakthrough therapy” for patients with advanced melanoma. The investigational antibody therapy targets the programmed death (PD-1) receptor, which cancer cells use to evade immune-system surveillance.
The FDA’s “breakthrough therapy” designation is intended to expedite the development and review of a candidate drug that is planned for use, alone or in combination, to treat a serious or life-threatening disease or condition when preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints.
In November 2012, early interim results were reported from a 12-week, single-arm, open-label phase Ib trial of lambrolizumab in 85 patients with advanced (inoperable and metastatic) melanoma. In that study, 43 patients (51%) showed an objective anti-tumor response, and of those, 8 patients (9%) showed a complete response at or after the 12-week assessment. The most common adverse events experienced by patients who received lambrolizumab included fatigue, rash, diarrhea, nausea, cough, joint pain, fever, and itching.
Lambrolizumab is an investigational antibody therapy designed to disrupt the action of the immune checkpoint protein PD-1, thereby inhibiting the ability of some cancers to evade the body’s immune system. Researchers have shown that several tumor types are able to “hide in plain sight” by establishing a “molecular camouflage” that deceives the body’s immune system into thinking they are normal and therefore allow them to grow unchecked. By using the PD-1 pathway, a tumor cell can prevent the activation of T-cells and may block a key step that triggers the immune system.
Advanced melanoma accounts for more than 80% of skin cancer-related deaths and for 1% to 2% of all cancer deaths in the U.S. According to the American Cancer Society, an estimated 9,180 people died from advanced melanoma in the U.S. in 2012.
Source: Merck; April 24, 2013.