Loren Data's SAM Daily™

FBO DAILY ISSUE OF MAY 17, 2003 FBO #0534
SOLICITATION NOTICE

Q -- Extended Safety & Preliminary Efficacy Trial for HIV Prevention among MSM

Notice Date

5/15/2003
 

Notice Type

Solicitation Notice
 

Contracting Office

Department of Health and Human Services, Center for Disease Control and Prevention, Procurement and Grants Office (Atlanta), 2920 Brandywine Road, Room 3000, Atlanta, GA, 30341-4146
 

ZIP Code

30341-4146
 

Solicitation Number

2003-N-00863
 

Response Due

6/16/2003
 

Archive Date

7/1/2003
 

Point of Contact

William Richardson, Contract Specialist, Phone 770-488-2653, Fax 770-488-2671, - William Richardson, Contract Specialist, Phone 770-488-2653, Fax 770-488-2671,
 

E-Mail Address

rtr4@cdc.gov, rtr4@cdc.gov
 

Description

Extended Safety of Once Daily Oral Tenofovir for HIV Prevention Among High-Risk Men who have Sex with Men A. PROJECT IDENTIFICATION AND PURPOSE: Post-exposure prophylaxis (PEP) with antiretroviral agents (ART) has been shown to substantially reduce the risk of HIV seroconversion after occupational exposures, and there is evidence to suggest that PEP may also reduce the risk after sexual exposures. The purpose of this project is to determine whether ART taken as pre-exposure prophylaxis (ie., before a sexual exposure occurs) is safe on a long-term basis. The agent chosen for the study is Tenofovir Disoproxil Fumarate (TDF) which is taken once daily and which has a strong safety and efficacy profile when used as a therapeutic agent. This study will be done in coordination with an independently sponsored trial that will examine the safety and efficacy of this agent among heterosexual women in Africa and Asia. Participants in this study will be randomized to receive either TDF or its placebo and will be followed for any adverse effects of the agent, any changes in their sexual behavior, and HIV incidence. Results of this study will determine whether TDF is safe and acceptable for long-term use among men who have sex with men (MSM), whether such use might affect participants? sexual behavior, and whether such use should be further investigated to demonstrate efficacy in preventing HIV acquisition among high-risk MSM. B. BACKGROUND AND NEED: The HIV epidemic is continuing to grow and the predominant mode of transmission worldwide is sexual. Sexual abstinence or consistent and correct condom use are the only methods currently recommended for prevention of sexually transmitted HIV yet many at-risk persons are either unwilling or unable to remain abstinent or to use condoms with every sexual act. An effective, easy to use method of prevention is urgently needed. Topical microbicides are being developed in hopes of offering at-risk persons a method to protect themselves from infection when condom use is not possible. However, no microbicide candidate has shown effective protection from HIV in human trials. Ever since the development of the first antiretroviral agents, the potential of ART to prevent HIV acquisition has been explored. Non-perinatal studies have looked at ART given as post-exposure prophylaxis, i.e., after a person has been exposed to HIV. PEP was shown to dramatically decrease the risk of HIV seroconversion among persons who had been occupationally exposed. Similarly, even though no definitive human studies of the efficacy of PEP for sexual HIV exposures exist, much animal and anecdotal evidence suggest that it may reduce the risk of transmission, and many healthcare providers currently offer it to persons who experience isolated exposures. PEP appears to have varying degrees of effectiveness depending on how long after the exposure it is given. This has raised the question of whether ART would be even more effective and potentially able to be used by greater numbers of at-risk persons if it were to be used before the exposure takes place, ie., as pre-exposure prophylaxis (PREP). Given the continued growth of the HIV epidemic and the relative lack of HIV prevention options, the concept of using a daily oral antiretroviral to prevent HIV transmission merits further exploration and testing. As noted above, condoms and potential topical microbicides require consistent and correct use during every coital act. This is similar to the situation when barrier methods were the most common forms of nonpermanent contraception. However, when hormonal oral contraceptives were introduced and the preventive method became disassociated with coitus, contraception became easier, popular, and more effective at the individual and population level. TDF has been selected for investigation as chemoprophylaxis against HIV in high-risk individuals because of its? unique pharmacologic profile. In addition to TDF?s convenience of being a once daily single tablet with a safety profile comparable to placebo among HIV infected persons, it has striking anti-HIV potency and a low potential for selection of resistant viruses. Each of these properties is necessary given the realities of the intended target populations. Moreover, initial prevention studies in simian models have provided encouraging results. An independently funded study is currently in the planning stages for an expanded safety and efficacy study of TDF among sexually active heterosexual women in Africa and Asia. Another population that is most likely to eventually use HIV chemoprophylaxis should it be proven to be safe and effective would be high-risk MSM, and thus it is imperative to determine in parallel with this international study whether TDF is safe for use by men. Of note, the public health policy issues associated with the use of oral HIV chemoprophylaxis may be substantially different for MSM as compared to heterosexual women in the developing world. As an example, there is concern that the potential for increased risk behavior may be greater for MSM. The availability of an oral agent may induce some men to switch from the most effective prevention method (condoms) to one that is less effective (TDF). It is likely that TDF may be highly effective against HIV (i.e., > 80%) but it has no efficacy against other sexually transmitted infections (STI) such as syphilis and gonorrhea. Modeling exercises have indicated that the availability of a less-effective method but which is used more often can result in a large decrease in HIV transmission. However, decreases in transmission of HIV would need to be considered in the context of the potential for increased transmission of other serious, although generally non-fatal STI. E-Mail: RRichardson@cdc.gov
 

Place of Performance

Address: Centers for Disease Control & Prevention, Koger Center, Colgate Bldg (PGO), 2920 Brandywine Rd, Atlanta, GA

Zip Code: 30341

Country: US
 

Record

SN00324723-W 20030517/030515213315 (fbodaily.com)
 

Source

FedBizOpps.gov Link to This Notice
(may not be valid after Archive Date)

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