FDA panel recommends approval of Merck pill for ragweed immunotherapy

The FDA Allergenic Products Advisory Committee voted Tuesday to recommend agency approval of Ragwitek, a new tablet form of ragweed allergen immunotherapy developed by Merck.

The advisory panel voted 8 to 0, with one abstention, regarding the drug’s safety data, and 6 to 2, with one abstention, in favor on Ragwitek’s efficacy. The drug is intended for patients aged 18 to 65 years.

Although no serious safety concerns were noted in FDA supporting documents released before the hearing, panel members voiced reservations about limited trial results for patients aged older than 50 years. All those panelists who either abstained or voted against approval said they would have voted “yes” if the approval technically stopped at patients aged 50 years, rather than at 65.

Panelist Jane W. Peterson, RN, PhD, said she hoped additional trials will include more non-Caucasian participants.

Other panelists suggested that future research should include children and also examine how patients would be affected by taking two or three times the recommended dose, urging that this be strongly discouraged in the prescribing information.

Ragwitek, a self-administered, under-the-tongue immunotherapy formulation for ragweed-induced rhinoconjunctivitis, does not require up-titration to achieve maintenance dosing.

The FDA is not obligated to follow the advisory committee’s recommendation, but often does.