Recently, the US FDA quietly released draft guidelines for clinical trials in rare pediatric diseases¹ that have a direct implication on the future of ocular gene therapy trials for retinal degenerations, paving the way for a more streamlined clinical development timeline. The major proposal in the draft guideline states that instead of requiring companies to run their own clinical trials against a control group, they can team up and run multiple experimental groups against a single control group. In other words, you could have, say, 4 different treatments from 4 different companies against a single control group — in one trial. Not only is this more ethical, offering patients a dramatically increased chance of being in the active treatment group, it also dramatically accelerates the development timetable. There are obviously a few basic rules that need to be followed in these multicompany trials, such as independent statistical analysis, independent data safety monitoring boards, and the need for long-term follow-up. Nevertheless, this could be a huge deal for retina specialists, as retinal degenerations certainly fit into the rare pediatric disease bucket.

The new FDA guidelines grew out of a partnership that started in 2011 with the European Medicines Agency to develop novel treatments for Gaucher disease. Although not specifically discussed in the guidelines, rare pediatric retinal degenerations have no effective treatments, and with so few patients for these clinical trials, they definitely fit the requirements. It remains to be seen if the FDA accepts this logic. If this were true, then many of the companies currently looking at choroideremia for example could combine forces, study costs, and patients into one clinical trial. The time and money savings would be immense. Unfortunately, it is unlikely that these same companies would pass on the cost savings to patients. As we recently witnessed with Spark’s Luxturna, gene therapy drugs will be very, very expensive.

One of the other interesting options in the draft guidelines is the ability to extrapolate efficacy data from adults to children as long as the disease course was expected to be similar. This is a big change, as in the past, expanding a drug into the pediatric population would have required a new trial in the pediatric population. The ability to test a drug in adults is much easier and cheaper. I truly hope the FDA Ophthalmic Division will also adopt these guidelines as it would be a great benefit to our patients. RP

REFERENCE

1. U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER). Pediatric rare diseases — a collaborative approach for drug development using Gaucher disease as a model guidance for industry. December 2017. Available at: https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM587660.pdf .