title: Injectable agents for pre-exposure prophylaxis: lessons learned from contraception to inform HIV prevention.
abstract: OBJECTIVE
  Long-acting injectable (LAI) forms of preexposure prophylaxis (PrEP) are in clinical trials, generating much hope for HIV prevention. But this is not the first time that an injectable form of preventive medication has emerged: the contraceptive agent depomedroxyprogesterone acetate (DMPA) has an important precedent. DMPA's long journey, its initial reception, and ongoing implementation challenges can help inform the field of HIV prevention as we plan for approval, acceptance, and scale-up of LAI-PrEP.
  
  
  RESULTS
  DMPA faced a long regulatory journey in the USA, with a lag of 25 years from initial application (1967) to approval (1992). Acceptance after introduction was rapid, but challenges hampered scale-up. Specific lessons learned include that extensive acceptability work is needed in parallel to product development. Also, low continuation rates, challenges with timing of initiation, and difficulty ensuring access for the most vulnerable populations have limited DMPA's impact. A new subcutaneous formulation presents opportunities for administration outside of clinical settings and for self-administration.
  
  
  CONCLUSIONS
  Those involved in LAI-PrEP development and those who plan to be involved in its future implementation must consider these lessons and possible solutions from DMPA to ensure a successful future for this new HIV prevention modality.
authors.affiliation: aBureau of HIV/AIDS Prevention and Control, New York City Department of Health and Mental Hygiene bDivision of Infectious Diseases, Department of Medicine, Columbia University, College of Physicians and Surgeons cICAP, Columbia University, Mailman School of Public Health dDivision of Family Planning and Preventive Services, Department of Obstetrics and Gynecology, Columbia University, College of Physicians and Surgeons eDepartments of Epidemiology and Population & Family Health, Columbia University, Mailman School of Public Health, New York, New York, USA.
authors.forename: Julie E
authors.initials: JE
authors.lastname: Myers
authors.forename: Tanya M
authors.initials: TM
authors.lastname: Ellman
authors.forename: Carolyn
authors.initials: C
authors.lastname: Westhoff
mesh_terms: D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D003267:Contraception / Q000379:methods*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000517:prevention & control*; D006801:Humans; D008297:Male; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage*; D065129:Pre-Exposure Prophylaxis / Q000379:methods*
chemical_list: D019380:Anti-HIV Agents; D017258:Medroxyprogesterone Acetate