Safety and Efficacy of RHH646 for Knee Osteoarthritis

Inclusion Criteria: * Participant is ≥35 and ≤75 years old, at time of screening * Participants must weigh at least 50 kg to participate in the study and must have a body mass index (BMI) ≤35 kg/m2. BMI = Body weight (kg) / \[Height (m)\]2 * Diagnosis of tibiofemoral OA in at least one knee by standard American College of Rheumatology clinical and radiographic criteria (Altman et al 1986) at screening * K\&L grade 2 to 3 OA in the target knee evaluated with X-Ray by the Central Reader at screening * Predominantly medial tibiofemoral compartment involvement defined as medial Joint Space Narrowing (medJSN) 1-2 (Altman et al 1995; Altman, Gold 2007) and medJSN \> lateral Joint Space Narrowing (latJSN) in the target knee evaluated with X-Ray by the Central Reader at screening * Symptomatic disease, defined as having pain in the target knee at least 3 days per week during the last 3 months from screening that is relieved by analgesic therapy (e.g. acetaminophen or non-steroidal anti-inflammatory drugs), according to the investigator's evaluation and judgment of the patient's history Exclusion Criteria: * Women of child-bearing potential, defined as all women physiologically capable of becoming pregnant, unless they are using highly effective methods of contraception. In EEA countries, women of child-bearing potential will be excluded from participation in this trial, irrespective of the use of highly effective methods of contraception. * Arthroscopy of the target knee within th…