Treatment News : First Data From Injectable PRO 140 Study - by Tim Horn

POZ - Health, Life and HIV
Subscribe to:
POZ magazine
Join POZ: Facebook MySpace Twitter Pinterest
Tumblr Google+ Flickr MySpace
POZ Personals
Sign In / Join

Back to home » Treatment News » February 2009

Most Popular Links
Most Popular Lessons

The HIV Life Cycle


Herpes Simplex Virus

Syphilis & Neurosyphilis

Treatments for Opportunistic Infections (OIs)

What is AIDS & HIV?

Hepatitis & HIV

20 Years Ago In POZ

More Treatment News

Click here for more news

Have news about HIV? Send press releases, news tips and other announcements to


February 12, 2009

First Data From Injectable PRO 140 Study

by Tim Horn

Delegates attending the 16th Conference on Retroviruses and Opportunistic Infections (CROI) in Montreal got a first look at data from a clinical trial testing injections of PRO 140, an experimental entry inhibitor. Two dosings were injected three weeks in a row; a third dose was injected every other week. The data, presented by Melanie Thompson, MD, of the AIDS Research Consortium of Atlanta on Monday, February 9, indicate that Progenics Pharmaceuticals, the drug’s developer, can abandon its original intravenous formulation of the drug and continue focusing on the subcutaneously administered formulation.

PRO 140 is a laboratory-made antibody that binds to a protein on the CCR5 membrane of CD4 cells. Once PRO 140 does this, HIV cannot successfully bind with the surface of CD4s; thus the virus is prevented from infecting healthy cells. While Pfizer’s Selzentry (maraviroc) works differently from PRO 140, both drugs target CCR5 and are considered HIV entry inhibitors.

The Phase II clinical trial results presented by Thompson’s group involved 44 people living with HIV who were either treatment naïve—they’d never been on antiretrovirals—or had been off HIV treatment for at least three months. Patients were randomized to receive three weekly doses of 162 mg PRO 140, two doses of 324 mg PRO 140 administered every other week, three weekly doses of 324 mg PRO 140, or placebo. Volunteers were followed for a total of 58 days to evaluate safety and antiviral effects of the drug compared with placebo.

On day 22 of the study—a week after the last dose of PRO 140 or placebo—a viral load reduction of 1.51 log was reported among patients receiving once-weekly 324 mg PRO 140, compared with an average 0.15 log increase in viral load among the placebo recipients. This finding was highly statistically significant, meaning the difference between the two groups was too great to have occurred by chance.

Statistically significant viral load reductions were also seen in patients receiving the lowest dose of PRO 140 (-0.75 log) and every-other-week dosing (-1.22 log) compared with placebo. More than 90 percent of patients receiving PRO 140, regardless of their dosing group, saw their viral loads decreased by at least 1 log.

Whether or not there were statistically significant differences between the three groups receiving active drug was not reported.

No significant differences in CD4 count increases during this short study were reported, though there was a trend toward greater CD4 gains among those in the highest PRO 140 dose group. 

Injection-site reactions were documented in several patients, although these were generally mild and resolved within a few days after drug administration. Other side effects, seen in all study groups, included headaches, diarrhea, constipation, high blood pressure and upper respiratory infections.

Progenics announced that it plans to move forward with Phase II development of PRO 140, using subcutaneous dosing, in light of these encouraging results.

Scroll down to comment on this story.


(will display; 2-50 characters)


(will NOT display)


(will display; optional)

Comment (500 characters left):

(Note: The POZ team reviews all comments before they are posted. Please do not include either ":" or "@" in your comment. The opinions expressed by people providing comments are theirs alone. They do not necessarily reflect the opinions of Smart + Strong, which is not responsible for the accuracy of any of the information supplied by people providing comments.)

Comments require captcha.
Please enter this number for verification:

| Posting Rules

Show comments (0 total)

[Go to top]

Facebook Twitter Google+ MySpace YouTube Tumblr Flickr Instagram
Quick Links
Current Issue

HIV Testing
Safer Sex
Find a Date
Newly Diagnosed
HIV 101
Disclosing Your Status
Starting Treatment
Help Paying for Meds
Search for the Cure
POZ Stories
POZ Opinion
POZ Exclusives
Read the Blogs
Visit the Forums
Job Listings
Events Calendar
POZ on Twitter

Ask POZ Pharmacist

Talk to Us
Has a pet helped you deal with your HIV?


more surveys
Contact Us
We welcome your comments!
[ about Smart + Strong | about POZ | POZ advisory board | partner links | advertising policy | advertise/contact us | site map]
© 2016 Smart + Strong. All Rights Reserved. Terms of use and Your privacy.
Smart + Strong® is a registered trademark of CDM Publishing, LLC.