HPTN 094 Trial: Mobile Units Cut All-Cause Mortality 71% in People Who Inject Drugs

The trial enrolled participants in Houston, Los Angeles, New York, Philadelphia and Washington DC who were not on MOUD at baseline. One arm received on-site PrEP, buprenorphine or methadone, limited primary care and harm reduction in mobile units; the control arm received referrals only. Verified daily oral PrEP use remained low in both arms at 26 weeks, while MOUD initiation reached 14% at 26 and 52 weeks, a meaningful shift from zero at enrollment. Mortality reduction occurred without differences in PrEP or MOUD uptake, suggesting mobile units improved engagement with acute care, wound management or overdose response.

Injection drug use drives roughly 10% of new US HIV diagnoses and clusters with hepatitis C and fatal overdose. Prior observational data from syringe-service programs show mobile delivery improves retention, yet few RCTs have tested bundled HIV-SUD services. The absence of PrEP effect aligns with CDC surveillance indicating oral PrEP acceptance below 10% among people who inject drugs, largely due to stigma and daily pill burden. Long-acting injectable cabotegravir or lenacapavir trials in this population are therefore the logical next step.

Policy implications include expanding mobile unit reimbursement under Medicaid and SAMHSA grants. Cities already operating integrated vans could add HIV testing and PrEP initiation within existing overdose-prevention infrastructure. Future studies must measure cost per life-year saved and assess whether mortality gains persist beyond 52 weeks when navigation ends.

Evidence gaps remain around which specific mobile services drove the mortality signal and whether findings generalize beyond the five trial cities with established harm-reduction networks.