Vismodegib exhibits activity against adult recurrent sonic hedgehog (SHH)-medulloblastoma but not against recurrent non-SHH medulloblastoma, a new study published online ahead of print in the Journal of Clinical Oncology has shown.
Researchers analyzed results from two phase 2 studies that assessed the efficacy of vismodegib, a SHH pathway inhibitor, in pediatric and adult patients with recurrent medulloblastoma.
Researchers enrolled 31 adult patients and 12 pediatric patients. All patients were treated with vismodegib 150 to 300 mg/day.
Results showed that three adult patients and one pediatric patient, all with SHH-subgroup medulloblastoma, achieved a sustained response for 8 weeks. Researchers found that progression-free survival was longer in patients with SHH-subgroup medulloblastoma compared with those with non-SHH-medulloblastoma.
The study also demonstrated that among those with SHH-medulloblastoma, loss of heterozygosity of PTCH1 was associated with prolonged progression-free survival, while diffuse staining of p53 was linked with reduced progression-free survival.
The findings suggest that further research is warranted to identify patients with certain genomic aberrations that will benefit the most.