This is a 12 weeks randomized, double-blind, placebo-controlled clinical study to assess the effect of Andrographis Paniculata at low dose of 300 mg/day and high dose of 600 mg/day in the study population in the age range of 40-70 years and suffering from mild-moderate OA.

In this study, we will assess the efficacy parameters such as effect on various joint health parameters (pain, stiffness and physical activity) by using WOMAC scale. The individuals with knee OA suffer from an increased impact on their activities of daily living, which leads to losses in labor relations, leisure, social life, and sleeping quality, leading also to important decrease in their quality of life. Thus, an important outcome to be evaluated in this study is quality of life of these individuals which will be assessed by SF-36 self-reported questionnaire. One of the aims of this study is therefore to investigate the levels of different dimensions of fatigue in knee OA and to assess changes in fatigue after the treatment targeting pain reduction and physical functioning by the use of FACIT-fatigue questionnaire.

Effect of the treatment on rescue medication consumption which is directly proportional to the degree of pain will also be captured via this study. The hepatic (SGOT and SGPT) and renal (serum creatinine) safety biomarkers will be assessed to investigate the effect of chronic use of Andrographis Paniculata on liver and kidneys.

Inclusion Criteria:

1. Male or female subjects in the age range of 40 - 70 years (both inclusive).
2. Body mass index (BMI) must be ≥ 25 and < 29.9 kg/m2.
3. Radiographic evidence of grade I- II osteoarthritis of knee joint, based on the Kellgren and Lawrence radiographic entry criteria with WOMAC pain score in range of 10-16.
4. History of primary idiopathic osteoarthritis of the knee characterized by pain of mild to moderate intensity which requires intake of analgesics.
5. Self-reported difficulty in at least one of the following activities attributed to knee pain: walking a distance of 400 metres, getting in and out of the car, going up and down the stairs or stiffness observed in the knee if > 30 minutes in the same position.
6. Female subjects of child-bearing age must be willing to use the accepted methods of contraception during the course of the study.
7. Ability to provide written informed consent.

Exclusion Criteria:

1. Prior or ongoing medical conditions (e.g. concomitant illness, psychiatric condition, alcoholism, drug abuse), medical history, physical findings, ECG findings or laboratory abnormalities that in the investigator's opinion could adversely affect the safety of the subject, makes it unlikely that the course of treatment or follow-up would be completed or could impair the assessment of study results.
2. History of surgery or major trauma to the study joint.
3. History of arthroscopic surgery or intervention on the study joint.
4. Subjects who have received intra-articular steroids or hyaluronic acid within the last three months.
5. Signs of active study joint inflammation including redness, warmth, and/or, if qualifying with osteoarthritis of the knee, a large, bulging effusion of the study knee joint with the loss of normal contour of the joint at the screening visit or at the baseline examination after the washout period.
6. Subjects awaiting a replacement of knee or hip joint.
7. Subjects with other conditions that cause pain.
8. Subjects with deformity of the knee joint.
9. Subject who are significantly incapacitated or disabled and would be categorized as ACR Functional Class IV (largely or wholly incapacitated), or unable to walk without assistive devices.
10. Subjects with other known rheumatic or inflammatory disease such as rheumatoid arthritis, osteomyelitis and bone metastasis.
11. Other pathologic lesions on X-rays of knee.
12. Positive hepatitis B surface antigen, Hepatitis C antibody, Anti human immunodeficiency virus (HIV) antibody test, or VDRL.
13. History of bleeding disorders.
14. Inability to comply with the protocol requirements.
15. Participation in any other clinical trial within 3 months of registering in this trial.
16. Women of child-bearing potential with a positive pregnancy test or who are lactating.