Abstract
Background
Ibalizumab-uiyk (IBA) was recently approved for the treatment of multi-drug-resistant HIV-1 infection in patients (pts) failing other antiretroviral regimens. Clinical trial data demonstrated a decrease in HIV-1 viral load in 83% and 43% of patients (n = 40) receiving IBA for 2 and 25 weeks (weeks), respectively. Real-world post marketing data are needed. This pilot study reports the experience of IBA utilization in POICs.
Methods
Medical records of patients receiving intravenous IBA from approval through April 2019 were reviewed. Data collected include demographics, infection and treatment history, IBA regimen and adverse events. Plasma HIV-1 RNA viral load (log10 copies/mL) and CD4 count (cells/µL) were collected at baseline and as available during therapy. Based on available follow-up (FU) labs, response was assessed at 4–10 weeks (FU 1), 14–22 weeks (FU 2), and 24–37 weeks (FU 3).
Results
Nine patients (mean age: 48 ± 11 years, 67% male) from 7 POICs received IBA for a median duration of 33 weeks (range 4–43). Median length of HIV-1 diagnosis was 22 years (range 8–25). Resistance to ≥1 drug in at least 3 drug classes was reported in 56%. All patients received at least one concurrent anti-retroviral agent. IBA was initiated at 2000 mg followed by 800 mg every 2 weeks. All patients received infusions as scheduled (151 total infusions) except for one requiring a second loading dose. Baseline mean CD4 count and viral load were 49 cells/µL and 4.9 log10 copies/mL, respectively. Labs obtained at FU 1 indicated a decrease in viral load of at least 0.5 log10 copies/mL in 6/8 patients (75%); a mean reduction of 2.1 ± 1.8 log10 copies/mL (Table 1). Mean HIV-1 titers available for patients at FU 2 (n = 6) and FU 3 (n = 7) were 3.1 ± 2.0 and 3.2 ± 2.6 log10 copies/mL, respectively. Mean CD4 counts were 65 ± 57 cells/µL at FU 1, 96 ± 61 cells/µL at FU 2 and 88 ± 82 cells/µL at FU 3. Adverse events were reported in 8 patients (89%), most common itching/rash, diarrhea and abdominal pain. None resulted in discontinuation of IBA.
Conclusion
This study confirms the antiviral activity of IBA in patients with advanced HIV-1 infection in the real-world setting. We observed well-tolerated therapy with an early reduction in HIV-1 viral load of 75%, followed by a 43% reduction ≥24 weeks, consistent with the clinical trial.
Disclosures
All authors: No reported disclosures.
Cell-Mediated Immune Predictors of Vaccine Effect on Viral Load and CD4 Count in a Phase 2 Therapeutic HIV-1 Vaccine Clinical Trial