Another Showdown in the Hyaluronic Acid Market?

Highly variable in terms of who will respond to treatment but efficacious in those who do, intra-articular injections of hyaluronic acid (HA) have become a standard part of the treatment regimen for knee osteoarthritis (OA) sufferers, filling the treatment gap between non-steroidal anti-inflammatory (NSAIDs) drugs and knee replacement. SmartTRAK estimates that over 2.1 million HA treatments (defined as a series of injections) will be administered in the US this year to patients with knee OA fueling a market projected to reach over $1B in 2017.

Cost in the Forefront

Recent studies have highlighted that intra-articular HA therapy represents a significant portion of the overall costs associated with managing patients with knee OA. A study published in the September 2016 issue of JBJS evaluating 244,059 candidates for knee replacement found that 14.7% had ≥1 HA injections in the 12 months preceding surgery. HA injections were responsible for 16.4% of all knee OA-related payments and accounted for 25.2% of treatment-specific payments.

At this year’s AAOS, another study entitled, “What Are the Costs of Knee Osteoarthritis in the Year Prior to Total Knee Arthroplasty?” further drives home the issue of cost associated with HA injections. The study, which received the AAHKS Clinical Research Award, reviewed the records of 86K total knee arthroplasty (TKA) patients from the Humana database to determine non-arthroplasty related costs, defined as reimbursement paid by an insurance provider, during the 12 months preceding knee replacement. In the year prior to TKA, the total cost associated with knee OA was $78.4K and the non-inpatient cost associated with the diagnosis of knee OA was $43.6K.

Approximately two-thirds of patients had at least one intervention in the year prior to surgery. Of the 8 treatments analyzed, only 3 (physical therapy, non-steroidal anti-inflammatories, tramadol) were strongly recommended by the AAOS and accounted for 12.2% of total non-inpatient knee OA cost, whereas the remaining 5 (hyaluronic acid injections, corticosteroid injections, knee brace, wedge insole, opioids) not recommended by AAOS accounted for 46.5% of non-inpatient cost associated with the diagnosis of knee OA. Approximately 30% of the total non-inpatient cost was attributed solely to hyaluronic acid injections. The authors concluded that if only AAOS-recommended treatments were employed, the cost for outpatient management of knee OA would decrease by 90%!

Payer Reaction: The Big Unknown

When the AAOS released the second edition of its recommended clinical practice guidelines (CPGs) for managing patients with knee OA in 2013, the society advised against HA injection therapy (along with PRP and growth factors) citing strong evidence against its use in the management of knee OA. While the initial impact of the CPGs on the HA market was short lived, it is yet to be seen how payers will react to this new data regarding cost.

Currently, there are seven companies promoting 12 approved HA products for knee OA in the US including 3 single injection, one 2-injection, five 3-injection and three 5-injection products. All products require the completion of IDE clinical studies in a specific indication of use before being granted FDA approved. As a result, there is a substantial base of clinical data supporting intra-articular HA injections as a treatment for pain relief associated with knee OA. While it is not known what percent of patients eventually undergo knee replacement surgery, it is surprising that the AAOS does not consider this data as adequate clinical evidence. In the meantime, manufacturers need to brace for possible fall-out now that the issue of cost is in the limelight and start looking for new technologies beyond HA for treating knee pain.