FDA's boceprevir review spotlights safety concerns

While offering a general endorsement of Merck's ($MRK) claim that its data demonstrates that boceprevir can effectively treat hepatitis C, an FDA staff review released this morning highlights some potential safety concerns that researchers will be grilled on during an expert panel review coming up on Wednesday.

According to Reuters, staffers' key concern is with the evidence of an increase in anemia among patients taking the drug, though a review of the agency's notes also indicates that the data was somewhat confusing for regulators. Psychiatric symptoms--such as suicidal and homicidal thoughts--also warranted a warning note, though reviewers added that it is "difficult to make any meaningful clinical conclusions" about the data.

The safety concerns, though, don't appear to be a deal breaker for Merck. Clinicians can take steps to identify anemia or psychiatric symptoms and take action if it is seen in patients. Analysts have given Merck and its rival Vertex--which is readying telaprevir for a review on Thursday--high marks for marshalling an impressive set of data to make their case with regulators. In addition, specialists in the field appear eager to get their hands on a pair of new treatments for the disease, replacing standard therapies which have limited cure rates and serious side effect issues.

Altogether, Merck and Vertex appear to be well positioned as they navigate a key hurdle on their way to a pair of expected landmark approvals.

- here's the FDA staff review
- read the story from Reuters