Popular HIV-Suppressing Drug Nelfinavir Adds Cancer Fighting to Its Repertoire

Author:  Jiang Dennis
Date:  October 2007

An HIV-suppressing drug may soon be prescribed to cancer patients. Nelfinavir (Viracept, Pfizer), a drug that hinders the HIV virus's ability to infect new cells, also has the ability to reduce the growth of certain cancer cells. This discovery is published recently in Clinical Cancer Research by researchers from the National Cancer Institute (NCI).

Of the six clinically approved HIV drugs used in the study, nelfinavir was the most potent and the most versatile – slowing down the growth of cancerous cells from 9 different tumor types. "Normally, you would expect activity against 1 or 2 tumor types, and not others," remarked senior author Philip Dennis, MD, PhD from the medical oncology branch of the NCI Center for Cancer Research. Some of the cancer cells whose growth has been inhibited by nelfinavir include non-small cell lung carcinoma and drug-resistant breast cancer cell lines.

Turning an already approved HIV drug like nelfinavir into a new anticancer drug is part of an exciting process called repositioning. The advantage of repositioning existing drugs is the speed at which these drugs may be approved by the Food and Drug Administration (FDA) for prescriptive usage. Dennis said in an interview that it took a year and a half to take nelfinavir through preclinical research and into clinical trials, and that a new chemical compound would likely require 5 years before clinical trials can be attempted. Such efficiency achieved through repositioning is possible because all the toxicological and safety data for these drugs are already available.

Eight million Americans die from cancer during the time a new anticancer compound is developing into an FDA-approved drug. Because of this, Dennis emphasizes that repositioning "can save years and millions of dollars" - not to mention millions of lives.

Nelfinavir's cancer fighting abilities have proven to be effective in cell cultures as well as in animal models. Currently 5 cancer patients are enrolled in the phase 1 study held by the National Institutes of Health Clinical Center, and another 40 patients are being recruited to complete the study.


1. Joell J. Gills et al. Clinical Cancer Research 2007:13(17) September 1, 2007

2. http://www.medscape.com/viewarticle/562527

3. http://www.atdn.org/simple/nelf.html

Written by Dennis Jiang

Reviewed by Pooja Ghatalia.