Clinical Trial Finder

Inclusion Criteria:

1. Symptomatic disease due to osteoarthritis, defined as a WOMAC Pain score ≥ 8 (worst possible = 20) 2. Focused Analgesia Selection Test will be used to determine whether patients can report pain with sufficient consistency to enter the clinical trial. 3. Males and females between 45 and 85 years of age, inclusive. 4. Kellgren-Lawrence grading of 2 or 3 within the last 6 months. 5. Stable analgesic regimen during the 4 weeks prior to enrollment. 6. In the judgment of the Investigator, acceptable general medical condition. 7. Life expectancy >6 months. 8. Male and female participants who are heterosexually active and not surgically sterile must agree to use effective contraception, including abstinence, for the duration of the study. 9. Have suitable knee joint anatomy for intra-articular injection. 10. Willing and able to return for the follow-up (FU) visits. 11. Able to read and understand study instructions, and willing and able to comply with all study procedures.

Exclusion Criteria:

1. Hypersensitivity, allergy, or significant reaction to any ingredient of the study drug, including double-stranded DNA, mannose, and sucrose. 2. Previously received XT-150 injection(s) 3. Scheduled partial or complete knee replacement within 6 months; participant agrees not to schedule a knee replacement during Stage A of the study. 4. History of knee arthroplasty on the Index Knee, i.e., selected for study injection(s) 5. History of rheumatoid arthritis or other inflammatory disease. 6. History of immunosuppressive therapy; systemic steroids in the last 3 months. 7. Received knee injection with hyaluronic acid or stem-cells in the last 6 months. 8. Knee injection of glucocorticoid in the last 3 months. 9. Current treatment with systemic immunosuppressive (systemic corticosteroid therapy or other strong immunosuppressant) 10. Currently receiving systemic chemotherapy or radiation therapy for malignancy. 11. Clinically significant hepatic disease as indicated by clinical laboratory results ≥3 times the upper limit of normal for any liver function test (e.g., aspartate aminotransferase, alanine aminotransferase) 12. Severe anemia (Grade 3; hemoglobin <8.0 g/dL, <4.9 mmol/L, <80 g/L; transfusion indicated), Grade 1 white cell counts (lymphocytes

- 800/mm3; 13. Positive serology for human immunodeficiency virus, hepatitis B virus, or hepatitis C virus. 14. Significant neuropsychiatric conditions; dementia, major depression, or altered mental state that in the opinion of the Investigator will interfere with study participation. 15. Current treatment with systemic antibiotics or antivirals (EXCEPTION: topical treatments) 16. Current anticoagulant or anti-platelet treatment (e.g., warfarin, heparins, factor X inhibitors, clopidogrel, prasugrel, ticagrelor, or dipyridamole). Low-dose (≤ 325 mg/day) aspirin is permitted. 17. Known or suspected history of active alcohol or intravenous/oral drug abuse within 1 year before the screening visit. 18. Use of any investigational drug or device within 3 months before enrollment or current participation in a trial that included intervention with a drug or device; or currently participating in an investigational drug or device study. 19. Any condition that, in the opinion of the Investigator, could compromise the safety of the participant, the participant's ability to communicate with the study staff, or the quality of the data

This is a Phase 2 safety and efficacy study of XT-150 in adult participants experiencing moderate to severe pain due to osteoarthritis of the knee. Baseline confirmation of study eligibility will be completed the day before or day of study drug administration. Study drug will be administered by intra-articular (IA) injection into the joint space of the knee. Up to 270 participants will be randomly enrolled into 1 of 3 treatment groups (90 participants/ group). Treatment Groups: 1. Placebo (1 mL) 2. Low dose XT-150 (1 mL) 3. High dose XT-150 (1 mL) The study will be conducted in 2 stages, A and B: A. Placebo-controlled for 6 months. B. Continued follow up for 6 months with the option of receiving one of two doses of XT-150 injection to the index knee. Final assessments will be 12 months after the first IA dose.

Arms

Placebo Comparator: Placebo

Inactive comparator

Experimental: Low Dose XT-150

Low dose active, experimental treatment

Experimental: High Dose XT-150

High dose active, experimental treatment

Interventions

Biological: - XT-150

plasmid DNA