All patients had progressive hearing loss at the start of the study, an enrollment criterium, whereas none of the patients experienced further hearing loss during the study. Bevacizumab was stopped in all patients after 12 months to assess how long the hearing improvement would last. The improvement was maintained for 6 months in 5 of 9 ears after the drug was stopped.
“The trial results, although limited by the small number of patients, suggest that patients may not need to get doses of drug as frequently as may be required for cancer and also may be able to take breaks in treatment. This may help reduce the frequency of negative side effects and control long-term health care costs,” said Blakeley.
Because bevacizumab costs up to $5,000 per dose and has potentially harmful side effects, the investigators caution that the treatment is not ready for general use in all patients with hearing loss due to neurofibromatosis. However, this study laid the groundwork for identifying the best candidates with NF2 for treatment with the drug and the optimal dosing.
1. Blakeley JO, Ye X, Duda DG, et al. Efficacy and biomarker study of bevacizumab for hearing loss resulting from neurofibromatosis type 2-associated vestibular schwannomas [published online ahead of print March 14, 2016]. J Clin Oncol. doi:10.1200/JCO.2015.64.3817.