A harm reduction model to assess the impact of new treatments for pain over standard of care among patients with osteoarthritis

BACKGROUND: Osteoarthritis (OA) affects millions of adults in the United States and can result in substantial pain, functional impairment, and significant clinical and economic burden. To manage chronic pain associated with OA, treatment guidelines recommend a variety of pharmacologic treatments, including traditional oral nonsteroidal anti-inflammatory drugs (NSAIDs), cyclooxygenase-2 inhibitors (COX-2s), and opioids. While these drug treatments can be effective at pain management, they are also associated with significant clinical and economic burden. New treatments for chronic pain among patients with OA of the hip and/or knee have the potential to reduce the occurrence of such negative clinical outcomes, including cardiovascular events, renal events, and opioid use disorder (OUD), thereby reducing health care resource use (HRU) and medical costs. OBJECTIVE: To develop a harm reduction model (HRM) to assess potential reductions of negative clinical outcomes, HRU, and medical costs associated with the use of new treatments in place of oral NSAIDs, tramadol, and non-tramadol opioids among patients with OA of the hip and/or knee in the United States. METHODS: The HRM model integrated findings from the literature and inputs from a variety of sources, along with assumptions regarding potential ability of new treatments to replace existing treatments and market penetration into a unified framework to estimate outcomes and costs. The model outputs included estimated per-patient and population-level reductions in negative clinical outcomes associated with prescribing new treatments in place of oral NSAIDs or opioids along with number needed to treat (NNT) associated with new treatments. The model assumed that new treatments will primarily be used in place of non-tramadol opioids, but more modest adoption in place of oral NSAIDs and tramadol. RESULTS: Among patients with OA of the hip and/or knee who were prescribed oral NSAIDs, tramadol, or non-tramadol opioids for chronic use (≥ 90 days), the HRM estimated total cost savings of $3.8 billion, $5.1 billion, and $29.9 billion, respectively, from prescribing new treatments for OA pain over a 36-month period. The reduced economic burden was driven by significant reductions in the incidence of negative clinical outcomes. Estimates of the NNT to avoid a negative clinical event related to NSAID and opioid treatment initiation were low for most outcomes. Estimates of NNT associated with NSAID use ranged from 4 to 17 patients, depending on outcome, and estimates of NNT associated with opioid use was 35 non-tramadol and 134 tramadol patients for OUD and ranged from 6 to 21 patients for the other clinical outcomes, depending on treatment and outcome. CONCLUSIONS: Results from the HRM suggest that prescribing new treatments in place of oral NSAIDs and/or opioids for OA pain results in a potentially substantial reduction in patients experiencing negative clinical outcomes and reductions in all-cause HRU and costs.