HIV Treatment Effectively Reduces Virus in Multi-Drug Resistant Patients

Phase 3 study results showed that the new HIV therapy ibalizumab reduced viral replication and increased immunity in drug-resistant patients.

A new HIV therapy demonstrated its efficacy in reducing the virus and boosting immunity in drug-resistant patients, according to a new study published in the New England Journal of Medicine.

The phase 3 trial evaluated the newly-approved treatment, ibalizumab, in 40 patients with advanced, multi-drug-resistant (MDR) HIV infection. A novel therapy, ibalizumab, works by targeting the primary receptor for HIV entry into immune cells, known as CD4 T cells.

For the study, the patients received an intravenous dose of ibalizumab in addition to their failing regimen for 1 week. Then, they received ibalizumab in combination with optimized treatment regimens for 6 months.

According to the study, the researchers found that ibalizumab decreased the viral load in 83% of enrolled patients after 1 week of treatment. After 25 weeks, nearly half of patients experienced a viral load suppression dip below the level of detection.

Additionally, the researchers reported an increase in CD4 T cells. One patient experienced an adverse event related to ibalizumab, which resulted in withdrawal from the study.

Individuals with MDR HIV face limited options when existing therapies fail to suppress the virus, leading to drug resistance and worsening disease. The findings indicate promise for patients who have otherwise run out of effective treatment options for their infection.

“These patients had extremely advanced HIV and resistant virus with limited options,” study co-author Brinda Emu, MD, Yale assistant professor of medicine, said in a press release. “To see viral suppression in a significant percentage of these patients at 6 months is heartening. The result represents a much-needed new mechanism of action for patients who have highly resistant HIV.”

In addition to its clinical benefits, ibalizumab’s novel mechanism means that it will not interact negatively with other medications, the researchers noted. Furthermore, the drug is administered every 2 weeks intravenously, as opposed to oral medications taken daily.

“It’s ushering in a whole class of medicine and a new mode of delivery for the treatment of HIV,” Dr Emu said. “I look forward to discussions in the community about how such a therapy will fit into the current treatment paradigm for HIV infection.”

Although the results are hopeful, the researchers cautioned that ibalizumab was approved based on a smaller number of patients treated, and patients and providers should remain vigilant for potential adverse effects.

References

Emu B, Fessel J, Schrader S, et al. Phase 3 study of ibalizumab for multidrug-resistant HIV-1. New England Journal of Medicine. 2018. Doi: 10.1056/NEJMoa1711460

New HIV therapy reduces virus, boosts immunity in drug-resistant patients [news release]. Yale’s website. https://news.yale.edu/2018/08/15/new-hiv-therapy-reduces-virus-boosts-immunity-drug-resistant-patients. Accessed August 16, 2018.