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# Changes Asked in Targeted Therapies Guidance
- URL: https://www.fdaweb.com/changes-asked-in-targeted-therapies-guidance/
- Published: 2018-02-21T12:00:00.000Z
- Updated: 2026-09-14T23:24:25.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5140811

BIO says FDA should expand a draft guidance on developing targeted therapies in low-frequency molecular subsets of a disease to provide further thinking on the agency’s receptivity to innovative approaches for developing targeted therapies. In its [comment](https://www.regulations.gov/document?D=FDA-2017-D-6617-0005&ref=fdaweb.com), BIO also recommends the draft guidance reflect a scenario in which one or more molecular alterations occur across multiple diseases.

In its comment [letter](https://www.regulations.gov/document?D=FDA-2017-D-6617-0010&ref=fdaweb.com), Pharmaceutical Research and Manufacturers of America reiterates the BIO request for a scenario of alterations across multiple diseases. The association also praises FDA for its efforts to advance development of targeted therapies in low-frequency molecular subsets of disease.

The National Organization for Rare Disorders [voices](https://www.regulations.gov/document?D=FDA-2017-D-6617-0007&ref=fdaweb.com) support for several aspects of the draft guidance and lists additional areas in which the draft could be improved, including additional clarity on how best to extrapolate data from studies conducted before the current development pathway.

Merck [asks](https://www.regulations.gov/document?D=FDA-2017-D-6617-0006&ref=fdaweb.com) FDA how strong the evidence from preliminary studies should be to support a grouping strategy. And it says the term “consistent” is used frequently in certain parts of the draft guidance but is not clearly defined, and guidance on criteria for establishing consistency would be helpful.