Published in the Bulletin of Experimental Treatments for AIDS April 1998 issue, by the San Francisco AIDS Foundation.

Selected Highlights from 5th Conf. on Retroviruses and Opportunistic Infections Main Page

• New Anti-HIV Drugs
• Hydroxyurea
• Protease Inhibitor and Other Drug Combinations
• Opportunistic Infections
• Miscellaneous

April 1998 Table of Contents

Main Page

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Selected Highlights from the 5th Conference on Retroviruses and Opportunistic Infections

Opportunistic Infections

Harvey S. Bartnof, MD

Can MAC Secondary Prevention be Stopped after HAART?

Anecdotal reports have been published of HIV positive patients who, after a sustained response to HAART and in consultation with their physicians, have discontinued secondary prophylaxis (preventive therapy) for either cytomegalovirus (CMV) retinitis or Pneumocystis carinii pneumonia (PCP). None have had a recurrence of either CMV or PCP. Prior to the era of HAART, after successful treatment for AIDS-related disseminated (blood borne) Mycobacterium avium complex (MAC), recurrence of MAC always occurred without secondary prophylaxis, due to severe immune deficiency.

Now, Judith Aberg, MD, and colleagues, from University of California San Francisco General Hospital (SFGH) have reported on 4 patients who were taken off secondary prophylaxis for disseminated MAC after a sustained response to HAART. After 5-10 months without prophylaxis, none have had a recurrence of disseminated MAC.

The SFGH researchers' study criteria included: 1) successful therapy for AIDS-related disseminated MAC, 2) 12 months or longer of secondary MAC prophylaxis, 3) negative cultures for MAC in both blood and bone marrow after 12 months, 4) no MAC symptoms and 5) HAART response with a CD4 count increased to greater than 100 cells/mm³ and an HIV RNA viral load decreased to less than 10,000 copies/mL. After discontinuing MAC prophylaxis, blood cultures for MAC were obtained after 4 weeks and then every 8 weeks.

The 4 patients who met the study criteria had a lowest CD4 count of 3-4 cells/mm³. They were taking 2-drug secondary prophylaxis for 4, 9, 9 and 12 months, respectively, at the time their MAC prophylaxis was stopped in 1997. At that time their CD4 counts had increased to 37, 202, 220 and 301 cells/mm³, respectively. Their HIV RNA viral loads were undetectable (limit of detection 500 copies/mL) for 3 of the 4, while the fourth had a viral load of 1,250 copies/mL. After discontinuing MAC prophylaxis, all subsequent blood cultures have been negative for MAC, and no MAC symptoms have recurred. All patients have continued HAART with sustained responses. The authors have called their patients' disseminated MAC "cured," however it would eventually return if HAART were discontinued or failed. The researchers are expanding their trial. People with HIV should consult their physician before stopping any drug therapy.

Aberg JA and others. Eradication of disseminated Mycobacterium avium complex (dMAC) in 4 patients after 12 months anti-mycobacterial therapy and response to highly active antiretroviral therapy (HAART). CROI. Abstract and poster presentation 729.

New CMV Eye Condition in People Responding to HAART

Researchers from the University of California at San Diego described a new clinical phenomenon in people with AIDS who have been treated for CMV retinitis, after starting HAART. A total of 15 patients developed retinal inflammation not previously observed in people with AIDS. The condition involved decreased vision or loss of vision in the eye that had previously been treated for CMV; patients did not experience pain. Physicians noted swelling of the macula (the part of the retina that is most important for vision) in addition to inflammation in the vitreous fluid in the back of the eye. In a minority of cases, an abnormal membrane developed at the retina. The condition occurred 2-20 weeks after CD4 cell counts had increased due to HAART. Many patients had undetectable blood HIV RNA viral loads at the time the condition occurred. All experienced improved vision after receiving steroid (Depomedrol) injections around the eye or oral steroid pills. This therapy did not reactivate their CMV retinitis.

Freeman WR and others. Ophthalmologic manifestations of immune recovery in AIDS patients. CROI. Abstract and poster presentation 757.

Herpesvirus Suppression with Acyclovir Decreases HIV Viral Load

Several times during the HIV/AIDS epidemic, herpesviruses have been associated with faster HIV/AIDS progression. At times they have been called a "co-factor" for HIV disease progression. Researchers from the University of Washington in Seattle have now presented new data that add to the evidence of a statistical association. They analyzed 29 participants (10% women) who were co-infected with HIV and herpes simplex virus type 2 (HSV-2). None were taking any anti-HIV therapy (this study was conducted prior to the HAART era). Median baseline HIV viral load was 30,000 copies/mL and median baseline CD4 cell count was 317 cells/mm³.

Patients were given suppressive therapy for their herpes infection with very high dose acyclovir (Zovirax), 800 mg every 8 hours for 8 weeks. The drug was withdrawn for 8 weeks, then started again for another 8 weeks. Plasma HIV viral load was measured monthly.

The results showed that while taking suppressive acyclovir therapy, median plasma HIV viral load was 7,300 copies/mL. When not taking acyclovir, viral load was 18,800 copies/mL. Acyclovir was statistically associated with a 63% reduction in HIV viral load. Patients took daily home cultures of their mouths, genitals and rectums that indicated asymptomatic HSV-2 shedding 15% of the time while not taking acyclovir and none of the time while taking the drug.

The hypothesis is that HSV-2 gene products may activate the HIV genome, thereby increasing HIV viral load. While this study was not performed using the standard HSV-2 suppressive acyclovir dose of 400 mg twice daily, it may be reasonable for HIV/AIDS patients co-infected with HSV-2 to take suppressive acyclovir therapy if they have incomplete HIV suppression with HAART or are intolerant of, unable to take or resistant to HAART medications.

Schacker TW. HSV suppression is associated with a significant decrease in plasma levels of HIV RNA. CROI. Abstract and oral presentation 260.

Short-Course Tuberculosis Prevention Effective in People with HIV

Researchers presented results indicating that tuberculosis prophylaxis consisting of 2 months of rifampin plus pyrazinamide is as effective as 12 months of isoniazid therapy. The study was a randomized trial of 1,583 HIV positive participants from the U.S., Mexico, Haiti and Brazil who tested positive on the PPD tuberculosis skin test; 28% of participants were women and 51% were African American or Haitian. One study arm received isoniazid 300 mg daily for 12 months. The other arm received rifampin 600 mg daily plus pyrazinamide 20 mg/kg daily, both for 2 months.

Participants were followed for a mean of 36 months. There were very low and nearly equivalent rates of confirmed or probable active tuberculosis and death in each arm. The difference in rates of adverse events was not significant (11% in the isoniazid arm and 12% in the combination arm). However, treatment completion rates differed significantly, with 68% of the isoniazid arm and 80% of the rifampin plus pyrazinamide arm completing therapy. The authors concluded that better adherence is likely associated with the higher completion rate in the 2-month combination regimen as prophylaxis for tuberculosis in people with HIV.

Harvey S. Bartnof, MD, has been a member of the Scientific Advisory Committee at the SF AIDS Foundation since 1987.

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