Title:  Process of determining the efficacy of drug treatment in HIV infected subjects

United States Patent:  6,210,875

Assignee:  Northwestern University (Evanston, IL)

Filed:  July 23, 1998

PCT NO:  PCT/US97/14870

102(e) Date:  July 23, 1998

PCT PUB. Date:  February 26, 1998

The present invention provides a process for determining the efficacy of anti-viral therapy in an HIV-infected subject receiving such therapy. The process includes the steps of a) detecting the level of transcriptionally active HIV in monocytes of the subject at a plurality of different times, b) comparing the detected HIV levels, and c) correlating changes in the detected HIV levels over time with the therapy. The process can be used to monitor the efficacy of treatment with any anti-HIV agent such as AZT, 3TC, DDC, Indivar, or Saquinavir. Decreases in HIV levels over time indicate an efficacious treatment. Increases in detected HIV levels over time indicate resistance to treatment.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a process of determining or monitoring the efficacy of drug treatment in HIV infected subjects. In accordance with this process, the levels of HIV RNA in monocytes of the subject are measured over the course of treatment with one or more drugs (e.g., AZT, 3TC, DDC). As drug treatment efficacy increases, the levels of HIV RNA in monocytes decreases. Conversely, where a subject develops resistance to a drug, that resistance is evident from an increase or lack of decrease in monocyte HIV RNA levels. In other words there is a direct correlation between the effectiveness of treatment and monocyte HIV RNA levels. Preferred monocytes for use in this invention are CD14⁺ monocytes.

In accordance with the present invention, dual immunophenotyping PCR in situ hybridization (DIPDISH) is used to detect cells containing HIV-1 DNA, dual immunophenotyping fluorescence in situ hybridization (DIPFISH) is used to detect and quantify gag-pol mRNA in cells and quantitative RNA analysis is used to quantify plasma viral load. The present invention discloses that monocytes, and particularly CD14⁺ monocytes, are persistently productive of HIV message. Furthermore, the levels of HIV mRNA in those monocytes respond in parallel with plasma viral load to drug therapy. As viral message production is an earlier event in virion production a process of the present invention is more a more sensitive indicator of drug efficacy and drug resistance than prior art methods.

Productively infected cell types in patients infected by HIV have been identified and quantified. As shown previously, very few CD4 positive lymphocytes were productively infected by HIV although many contain proviral DNA. The present invention discloses that monocytes are the major productively infected cell type in HIV seropositive individuals and viral production in these cells is altered by antiretroviral therapy. The percentage of productively infected monocytes corresponded with viral burden analysis in patients on no, single, combination, and triple drug therapy.

Claim 1 of 10 Claims

What is claimed is:

1. A process for determining the efficacy of anti-viral therapy in an HIV-infected subject receiving such therapy, the process comprising the steps of:

a) detecting the level of transcriptionally active HIV in monocytes of the subject at a plurality of different times by simultaneously exposing the monocytes to an oligonucleotide probe that specifically binds to at least a portion of HIV mRNA and exposing the monocytes to an antibody, wherein the oligonucleotide probe is labeled with a fluorescent label;

b) comparing the detected HIV levels; and

c) correlating changes in HIV levels over time with the therapy to determine the efficacy of the anti-viral therapy is the subject.

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