FDA approves J&J drug-Darzalex for advanced multiple myeloma

In one 106-patient study, tumors shrank or were no longer detectable in 29 percent of patients taking Darzalex, and the benefit lasted for an average of 7.4 months. In a second trial, involving 42 patients, 36 percent of patients taking the J&J/Genmab drug saw a partial or complete reduction in tumors.

Researchers said it is the first antibody drug to demonstrate effectiveness against myeloma without having to be combined with other medicines.

The most common side effects of the treatment included fatigue, nausea, back pain, fever and cough.

An estimated 26,850 Americans are expected to be diagnosed with multiple myeloma in 2015.

All patients eventually become resistant to existing therapies, which include Takeda's Velcade and Celgene's Revlimid, as well as newer drugs Kyprolis from Amgen and Celgene's Pomalyst.