76 - Efficacy of Subcutaneous Tanezumab for the Treatment of Osteoarthritis Across Age Groups: A Subgroup Analysis of Pooled Data from Two Randomized, Placebo-Controlled Trials

¹Independent Nurse Practitioner, Ponte Vedra Beach, Florida, USA. ²Altoona Center for Clinical Research, Duncansville, Pennsylvania, USA. ³University of California, San Diego, California, USA. ⁴Eli Lilly and Company, Indianapolis, Indiana, USA. ⁵Pfizer Inc., New York, New York, USA

Purpose
Tanezumab is a monoclonal antibody that binds nerve growth factor and stops it reaching its receptors. In patients with osteoarthritis (OA), subcutaneous tanezumab significantly improves pain, physical function, and patient’s global assessment of OA. The purpose of this pooled, post-hoc subgroup analysis, was to explore the efficacy of subcutaneous tanezumab in patients with OA of different ages.
Methods
A pooled exploratory analysis of patient level datafrom two randomized, placebo-controlled, Phase 3 trials (NCT02697773 and NCT02709486) of subcutaneous tanezumab (2.5 mg or 5 mg every 8 weeks for 16 or 24 weeks) in patients aged ≥18 years with moderate-to-severe knee or hip OA. In one trial, tanezumab was titrated from 2.5 mg at baseline to 5 mg at Week 8. This data is included in the pooled 5 mg group. Co-primary endpoints were change from baseline in Western Ontario and McMaster Universities OA Index (WOMAC) Pain (0 to 10; increasing pain), WOMAC Physical Function (0 to 10; increasing difficulty), and Patient Global Assessment of OA (PGA-OA; 1 to 5; increasingly poorer assessment) scores. Efficacy results are presented for the overall pooled population and age subgroups (<65, ≥65, <75 and ≥75 years) as the LS mean change from baseline to Week 16 versus placebo with 95% confidence interval.
Results
In the overall pooled population comprising patients of all ages, both doses of tanezumab were associated with significantly improved WOMAC Pain, WOMAC Physical Function, and PGA-OA scores at Week 16 compared to placebo (p<0.05). Somewhat similar improvements were observed in all age subgroups (grouped as <65 years [placebo n = 293; 2.5 mg n = 286; 5 mg n = 265], ≥65 years [220; 227; 252], <75 years [455; 457; 453], and ≥75 years [58; 56; 64]). In the pooled population, change in LS mean WOMAC Pain score over placebo (n = 513) was -0.7 (-0.95, -0.37) and -0.7 (-0.99, -0.41) in the 2.5 mg (n = 513) and 5 mg (n = 517) tanezumab groups, respectively. In the age subgroups, change over placebo ranged from -0.5 to -1.1 for both tanezumab doses. In the pooled population, change in LS mean WOMAC physical function score over placebo was -0.7 (-1.00, -0.42) and -0.8 (-1.08, -0.50) in the 2.5 mg and 5 mg tanezumab groups. In the age subgroups, change in over placebo ranged from -0.5 to -1.1 for both tanezumab doses. In the pooled population, change in LS mean PGA-OA score over placebo was -0.2 (-0.30, -0.09) and -0.3 (-0.36, -0.15) in the 2.5 mg and 5 mg tanezumab groups. In the age subgroups, change over placebo ranged from -0.2 to -0.4 for both tanezumab doses. Changes observed for the three outcomes were statistically significant compared to placebo (p<0.05 unadjusted) for all age and dose combinations except 2.5 mg in the ≥75 years subgroup, possibly due to low n. However, this exploratory post-hoc analysis was not part of the pre-specified hypothesis testing plan or included in any sample size calculations; therefore, comparisons between treatment or age subgroup should be conducted with caution.
Conclusions
When considering short-term use of subcutaneous tanezumab for the treatment of OA in specific patients, age does not appear to influence improvements in pain, function, and PGA-OA.