The purpose of this study is to assess the safety and efficacy of the SL-1002 injectable formulation, compared to placebo, for the treatment of knee pain associated with osteoarthritis. The study will be conducted in two parts referred to as Phase A and Phase B. In Phase A of the study, there will be a total of 3 dosing groups of subjects. Phase B of the study will enroll a single group of subjects. This study will last approximately 26 weeks, which includes a screening period that includes 2 visits. After the first two screening visits and the study drug treatment visit (Day 0), the subject will be required to return to the study site for 7 additional study visits at approximately 2 days, 1 week, 2 weeks, 1 month, 2 months, 3 months, and 6 months after the study drug treatment is administered on Day 0.