> ## Content Index
> Fetch the complete content index at: https://www.fdaweb.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# FDA ‘Refuse to File’ on HIV Drug
- URL: https://www.fdaweb.com/fda-refuse-to-file-on-hiv-drug/
- Published: 2020-07-14T12:00:00.000Z
- Updated: 2026-09-14T16:21:00.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5147195

FDA has issued CytoDyn a refusal to file letter on its BLA for leronlimab (PRO 140), a CCR5 antagonist used in combination therapy with highly active antiretroviral therapy for highly treatment-experienced HIV patients. FDA’s letter said the BLA does not contain certain information needed to complete a substantive review and therefore it could not be filed, the company says. CytoDyn says it will request a Type A meeting with FDA to discuss its request for additional information. It adds that the request does not require any additional clinical trials to be conducted, rather it will conduct additional analysis of completed trials.

Leronlimab is described as an investigational humanized IgG4 monoclonal antibody that blocks CCR5, a cellular receptor that is important in HIV infection, tumor metastases, and other diseases. The company says that leronlimab has completed nine clinical trials in over 800 people, including meeting its primary endpoints in a pivotal Phase 3 trial (leronlimab in combination with standard antiretroviral therapies in HIV-infected treatment-experienced patients). CytoDyn has been granted a fast track designation and a rolling review for the BLA. The therapy is also being studied in metastatic triple-negative breast cancer.