Christopher Evans, PhD, Mayo Clinic, Rochester, MN, describes interim results of an ongoing Phase I dose escalation study (NCT02790723) evaluating the safety and tolerability of an adeno-associated virus (AAV) vector encoding the human interleukin-1 receptor antagonist (IL-1Ra) in patients with knee osteoarthritis (OA). Nine patients with mid-stage OA that had not responded to conventional therapy received an intra-articular injection of the gene therapy vector into one knee and were followed up for one year. Results have demonstrated the safety and tolerability of the therapy, with only one adverse reaction of swelling following injection, which have prompted plans for a Phase II trial to evaluate therapeutic effect. This interview took place during the American Society for Cell & Gene Therapy 24th Annual Meeting 2021.