How do you determine if a drug is effective? Typically, biostaticians rely on a randomized control trial where half the patients receive the treatment of interest and the remaining half receive either a placebo or the current standard of care depending on the trial design.
Recent advances in cancer, however, call for more sophisticated designs. Some cancer treatments are only effective for patients with specific biomarkers; this treatment heterogeneity complicates the trial design. Further, some new treatments–such as immuno-oncology therapies–may improve health for patients with multiple tumor types.
How do biostasticians deal with these issues?
Richard Simon of the National Cancer Institute discussed two specific trial types in a recent AMCP article.
- Umbrella trials: Umbrella studies are designed to test the impact of different drugs on different mutations in a single cancer type…The trial design can help to facilitate patient screening and accrual, and is quite suitable for trials examining low-prevalence diseases. The primary features of umbrella trials are: (i) the inclusion of multiple treatments and multiple biomarkers within the same protocol, (ii) a design that allows for randomized comparisons, (iii) a design that can have flexible biomarker cohorts, and (iv) a design that can add/drop biomarker subgroups.
- Basket trials: Basket studies are designed to test the effect of a single drug on a single mutation in a variety of cancer types. They provide a unique way of merging the traditional clinical trial design with rapidly evolving genomic data that facilitate the molecular classification of tumors. Basket trials can also screen multiple drugs across many cancer types. A basket design provides evidence for pairing a drug with a validated biomarker in a specific tumor.