Treataware

Researchers have developed a new "assassin cell" therapy for treating HIV which involves engineering the patient's own immune system to fight the virus more effectively. The therapy - which has proved effective in laboratory tests using human cell cultures - will be tested in a clinical trial of 35 patients with advanced HIV infection that is due to start next summer.

With more than 20 antiretroviral drugs to choose from, one of the most frequently asked questions is what is the best regimen to start with in terms of efficacy and safety?

Currently the two nucleoside/nucleotide reverse transcriptase inhibitor (NRTI or nuke) backbones that are recommended by U.S. HIV treatment guidelines as part of a first-line regimen are abacavir/lamivudine (Kivexa) and tenofovir/emtricitabine (Truvada; also combined with efavirenz in the Atripla pill).

Raltegravir (Isentress), the new integrase inhibitor manufactured by Merck, showed equivalent anti-HIV activity to efavirenz during the first 48 weeks of a large phase III trial in treatment-naive patients, and those who received raltegravir had greater increases in CD4 counts and fewer central nervous system symptoms, delegates heard at the 48th Interscience Conference on Antimicrobial Agents and Chemotherapy on Sunday October 26 in Washington DC.

http://www.aidsmap.com/en/news/304C1C07-74B9-44CE-8906-84772A200B2F.asp

According to an analysis of data from a very large North American cohort collaboration, starting antiretroviral therapy at a CD4 cell count between 351-500 cells/mm3 results in a better likelihood of survival. The results were presented to the 48th Interscience Conference on Antimicrobial Agents and Chemotherapy in Washington DC on Sunday by lead investigator Mari M Kitihata, on behalf of the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD).

http://www.aidsmap.com/en/news/E20B6317-139E-449B-9978-4FC8D8B6259F.asp

Pre-existing resistance may reduce the efficacy of the protease inhibitor darunavir, a study published in the September 12th edition of AIDS suggests. French investigators found that both baseline protease inhibitor resistance and darunavir treatment which did not fully suppress viral load were associated with the emergence of mutations conferring resistance to darunavir. The authors suggest guidelines to reduce development of darunavir resistance in people who have previously taken protease inhibitors.
http://www.aidsmap.org/en/news/9938B4E7-FC17-46CE-BAEB-D89540C570D1.asp

In a meta-analysis of data from nearly 8000 patients reported in Clinical Infectious Diseases, researchers found significantly fewer drug resistance mutations, including NRTI-associated mutations, in people who had experienced treatment failure while taking first-line HIV treatment based on boosted PIs than in people taking NNRTI-based therapy.

The Pfizer Inc. AIDS drug maraviroc helps thwart the HIV virus in nearly half of people who have developed resistance to other treatments, according to two related studies published on Wednesday.

At least 42 percent of patients in Europe, North America and Australia who took maraviroc once or twice a day on top of standard drug cocktails had blood virus counts below levels that cause visible damage to the immune system.

Only 18 percent of patients who got a placebo plus a standard HIV drug combination got their viral levels that low over the 48 weeks that have been studied so far.

Abacavir-based regimens are slightly more cost-effective than tenofovir-based ones, a US mathematical modelling study published in AIDS has concluded. But this is only the case if patients are tested at the outset for the abacavir hypersensitivity reaction, a potentially fatal allergy to the drug.

The introduction of the fixed-dose NRTI combination pills Kivexa (abacavir and 3TC, called Epzicom in the US) and Truvada (tenofovir and FTC) in summer 2004 “ushered in a new treatment era for antiretroviral-naïve patients initiating antiretroviral therapy”, write American researchers in the October 1st edition of AIDS. After the introduction of these combination pills, the investigators found that the amount of time patients remained on first-line treatment increased significantly.

Ezetimibe significantly lowers LDL cholesterol in patients taking HIV treatment, American researchers report in the October 15th edition of Clinical Infectious Diseases. The researchers found that mean LDL cholesterol levels were a “meaningful” 11% lower after six weeks of treatment with the drug.

HIV-positive patients may have an increased risk of heart disease, and it is possible that this is due in part to the increases in LDL cholesterol caused by some antiretroviral drugs.