Siddarth Padia (David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, USA) presented six-month data from the “first” randomised controlled trial (RCT)—GRAVTIY—to demonstrate genicular artery embolization (GAE) as superior to best supportive care for knee osteoarthritis (OA).
Padia reported the data during a FIRST@CIRSE session at the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) annual congress (5–9 September, Copenhagen, Denmark).
Results showed that, among 119 patients aged 40–79 years with Kellgren-Lawrence grade ≥2 OA who had previously failed conservative therapy, 50% achieved ≥50% reduction in Western Ontario and McMaster Universities (WOMAC) at six months compared to 10.7% undergoing observation. The investigators also grouped patients by ≥75% and ≥90% WOMAC reduction, reporting a 31.5% and 7.4% decrease for GAE and 3.6% and 0% decrease for observation, respectively.
Meeting its primary endpoint, Padia noted that GRAVITY is the first positive trial to show a superior clinical improvement for GAE in moderate-to-severe knee OA.
Rather than determining the mean decrease in symptom severity at each timepoint, Padia detailed that a landmark primary endpoint was assigned so as to avoid a placebo effect, which is commonly seen in GAE trials. “We set the bar high, as it’s almost impossible to exceed a 50% improvement in WOMAC with placebo alone”, he said.
Patients were treated with 100µm Embozene (Varian) with an average procedure time of 88 minutes.
“We found that, at all timepoints, GAE was superior to observation in terms of WOMAC score and pain scores on a scale of 1–10,” Padia shared.
Of note, 18 adverse events were reported; six unrelated events to the initial GAE procedure and 12 related events, including eight skin ulcers, bruising at the arterial access site, nausea from naproxen following GAE, a single small bone infarct and one report of leg swelling. Padia noted that no treatment-related serious adverse events.
During audience questions, session moderator Ziv Haskal (University of Virginia School of Medicine, Charlottesville, USA) queried the percentage of patients who had experienced increased pain following GAE that could potentially be attributed to over embolization with a permanent embolic. To this, Padia responded that increased pain and stiffness during the first two weeks is typically expected, but “there wasn’t a single patient at one month who had increased pain compared to baseline”.
Pausing twice for applause during his talk, Haskal spoke on behalf of the CIRSE audience to commend Padia and his team of investigators for their “groundbreaking” efforts in obtaining these data.
Concluding, Padia stated that the long-term “goal” is to secure GAE among guideline recommendations that have positioned knee arthroplasty as the “gold standard” for several decades. As the first positive RCT in the GAE space, Padia hopes that their data will “propel the technique forward” in future recommendations for the treatment of knee OA.
