FDA Uses Kalydeco and Keytruda as Examples of How It Is Promoting Precision Medicine

The U.S. Food and Drug Administration is promoting a targeted treatment approach known as precision medicine to help people with diseases stemming from specific, and often rare, genetic features.

Its efforts include expanding the use of approved therapies to other genetic-based conditions, and pushing for the development of more biomarkers of diseases.

Two recent agency approvals exemplify that the approach is working, Dr. Janet Woodcock, director of the FDA’s Center for Drug Evaluation and Research, wrote in a blog on the FDA Voice website.

The article dealt with the expanded approval of Vertex’s Kalydeco (ivacaftor) for patients with a range of rare mutations in the CFTR gene that causes cystic fibrosis. The title of the blog is “Two Recent Scientific Advances Underscore an Encouraging Future for Precision Medicine at FDA.”

The agency’s decision to increase the number of mutations that Kalydeco can treat from 10 to 33 was based on results of non-human studies rather than clinical trials.

Regulators are increasingly using this approach because it can benefit patients with genetic features so rare that clinical trials of new therapies are difficult to carry out.

Merck‘s Keytruda (pembrolizumab) is another precision medicine example, Woodcock said. The FDA approved it for people with certain cancer-related genetic features rather than a specific type of cancer.

These are only two of more than 25 precision-medicine-type treatments the FDA has approved in the past three years, she said. In addition, it has expanded the conditions that many other drugs that are already on the market can treat.

To continue expanding the use of precision medicine, scientists need to keep making biomarker advances, she said.

Biomarkers measure biological features that tell researchers something about a disease — such as the presence of bacteria in airways or levels of an inflammatory molecule.

Among other things, biomarkers can help assess the severity of a condition, determine which patients are likely to respond to a treatment, and predict a disease outcome. They can also play a key role in drug development, Woodcock argued. A suitable marker can make it easier and faster for scientists to recruit the right type of patients for a clinical trial.

Biomarkers can also offer scientists a more sensitive measure of a treatment’s effectiveness. They do this by identifying measures of patient improvement before their symptoms get better.

To develop biomarkers, researchers need a detailed understanding of both a disease and its response to treatment. But identifying a biomarker is not enough. Scientists must confirm that it measures what they think it measures.

To help assure this, the FDA is working with scientists and others in a Biomarker Qualification Program. It allows any drug developer to use a validated biomarker, further advancing the development process.

“We believe it is important to make drugs such as Kalydeco and Keytruda available to as many patients as can benefit from them,” Woodcock said, adding that the “FDA is actively pursuing more advances in targeted therapies.”