RESUMO
Objectives: To evaluate purified honey bee (Apis mellifera) venom (HBV) biotherapy for the treatment of osteoarthritis (OA) knee pain and physical function. Design and Patients: Five hundred and thirty-eight patients with Kellgren/Lawrence grade 1-3 radiographic knee OA and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score ≥2 were randomized 1:2 to either control ("histamine") or HBV in this double-blind study. Interventions: After a dose escalation period, patients received 12 weekly dermal injections of control ("histamine") or HBV. At each of the 12 weekly visits, a set of 15 dermal injections (each containing 2.75 µg histamine or 100 µg HBV) were administered at prespecified acupuncture points (5 on each knee: knee top, eye-1 medial, eye-2 lateral, ST 34, BL 40 and 5 near the spinous processes: BL 19, 21, 23, 25, and 27). Outcome Measures: Assessments included WOMAC pain and physical function subscales, visual analog scale (VAS), patient global assessment (PGA), and physician global assessment (PhGA). Rescue medication use (acetaminophen) and routine safety parameters were monitored. Results: HBV biotherapy demonstrated a highly significant improvement over control in WOMAC pain score after 12 weeks (1.1 U mean difference; confidence interval [95% CI]: 0.3-2.0; analysis of covariance [ANCOVA] p = 0.0010 with baseline as covariate) that was also sustained 4 weeks post-treatment. Furthermore, WOMAC physical function was significantly improved over control with HBV (3.1 U mean difference; 95% CI: 0.3-5.9; ANCOVA p = 0.0046), and sustained 4 weeks post-treatment. VAS scores were significantly improved with HBV versus control, as well as PGA and PhGA evaluations, which showed that patients responded more favorably ("very good/good") to their overall OA condition (82.0% vs. 62.4% [p = 0.0001] and 82.1% vs. 54.9% [p = 0.0015], respectively). Use of rescue acetaminophen was similar between the groups (77%-78% of patients). HBV was associated with higher incidence of injection site reactions (<5%); however, the overall safety profiles were comparable between the treatment groups. Conclusions: This phase 3 trial demonstrated that HBV biotherapy resulted in significant improvements in knee OA pain and physical function.