FDA Approves New Options for Plague, Cystic Fibrosis


The FDA has approved Avelox (moxifloxacin) for the treatment of patients with plague, specifically pneumonic plague (infection of the lungs) and septicemic plague (infection of the blood), and for prevention of plague in at-risk adult patients.

Because of the rarity of plague, Avelox was approved under the FDA’s Animal Efficacy Rule, in which results of well-controlled animal studies are used when it is not feasible or ethical to conduct human trials.

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In a study of 20 African green monkeys infected with Yersinia pestis, the bacteria responsible for plague, all 10 monkeys given Avelox and none of the 10 given placebo survived.

The safety of Avelox was garnered from materials related to the drug’s existing clinical uses. Common side effects include nausea, diarrhea, dizziness, and headache. Other possible side effects include tendinitis in patients with the neuromuscular disorder myasthenia gravis, liver damage, blood abnormalities, and abnormal heart rhythm.


Orkambi - Cystic Fibrosis

An FDA advisory committee has recommended that the experimental drug Orkambi (a combination of lumacaftor and Ivacaftor) for the treatment of patients with cystic fibrosis (CF) and 2 copis of the F308del gene mutation. Patients with this gene mutation represent the largest population of individuals with CF.

CF is a rare genetic disease caused by mutations in the CFTR gene, resulting in a low number of functional CFTR proteins at the surface of cells, which help to regulate the flow of salt and water in and out of cells. Orkambi works by increasing the number of funtional CFTR proteins found at the cell surface.

Orkambi combines ivacaftor, the main ingredient in Kalydeco, another drug approved for the treatment of CF, with a new drug, lumacaftor. Overall, Orkambi showed only modest effectiveness, improving lung function by 3% over placebo, leading to questions about whether the inclusion of lumacaftor affected the effectiveness of ivacaftor alone.

In the end, due in part to the lack of new safety concerns with the addition of lumacaftor, the advisory committee voted 12-1 to approve the combo drug.

The FDA is expected to give its final decision by July 5.

—Michael Potts


1. FDA. FDA approves additional antibacterial treatment for plague [press release]. May 8, 2015.

2. Vertex. Food and Drug Administration Advisory Panel Voted 12 to 1 to Recommend Approval of ORKAMBI™ (lumacaftor/ivacaftor) to Treat People with Cystic Fibrosis Ages 12 and Older Who Have Two Copies of the F508del Mutation [press release]. Accessed May 12, 2015.