a study of the efficacy and safety of 2px in patients with pain due to osteoarthritis of the knee

Conditions: Pain; Osteoarthritis

Summary: the purpose of the study is to demonstrate the superiority of topically administered 2px versus placebo (vehicle) control in terms of reduction in pain intensity and physical function.

primary objective: to demonstrate the superiority of topically administered 2px versus placebo (vehicle) control in terms of reduction in pain intensity and physical function. secondary objectives: to prospectively measure other efficacy variables of topically administered 2px in pain associated with osteoarthritis of the knee. to evaluate the safety and tolerability of topically administered 2px.

Eligibility criteria:
inclusion criteria: * male and female out-patients, 40 years or older. * subjects with documented oa of either one or both knees, as defined by the american college of rheumatology (acr) criteria (\[altman r, asch e, bloch d, et al (1986)\]); i.e.knee pain and at least 3 out of the following 6 criteria in the target joint: * age \>50 years * stiffness \< 30 minutes * crepitus * bony tenderness * bony enlargement * no palpable warmth * radiological evidence of joint space narrowing in the target joint within 8 weeks prior to randomisation. * subjects with chronic, moderate to severe oa pain of the target knee: * present for more than 3 months, and for ≥ 20 days per month. * not controlled by, or intolerant of, oral nsaids, paracetamol, cox-2 inhibitors or weak opioids. * intensity at least moderate (i.e., actual womac (pain questions 1-5) ≥ 10) on womac oa index lk 3.1 at visit 1, in the target knee, as recalled over the last 24 hours. exclusion criteria: * subjects with any moderate to severe pain of other origin (e.g., fibromyalgia) which could confound assessment or self-evaluation of pain due to oa in the target knee. * subjects with any prosthesis fitted to the target knee. * subjects requiring treatment with any of the following agents/therapies within the specified periods or at any time during the study are excluded from participation: * any potent/strong opioid in the 4 weeks prior to randomisation (i.e., an opioid assumed to cause withdrawal symptoms upon abrupt discontinuation). * any topical or subcutaneously applied analgesic agents (e.g., capsaicin, nsaids) applied to the target knee within 7 days prior to randomisation. * any treatment which could alter the degree or nature of baseline oa pain planned within the study period. * intra-articular injections of corticosteroids in the target knee within the 2 months prior to randomisation. * intra-articular injections of hyaluronan in the target knee within 6 months prior to randomisation. * avascular necrosis in the target knee within 6 months prior to randomisation. * arthrosynthesis of the target knee within 12 months prior to randomisation. * arthroscopy of the target knee within 6 months prior to randomisation. * major trauma to the target knee within 6 months prior to randomisation. * infection in the target knee within 6 months prior to randomisation. * subjects who have previously been treated with 2px. * subjects who have received an investigational drug or used an investigational device within the 30 days prior to randomisation. * subjects with a significant psychiatric disorder, in the opinion of the investigator, or subjects receiving strong anti-psychotic medication. * subjects with documented or suspected alcohol or drug abuse. * any ongoing or past history of malignant disease within the 5 years immediately prior to randomisation (with the exception of basal cell carcinoma). * pregnancy or ongoing lactation * female subjects of childbearing potential unwilling to use adequate contraceptive measures throughout the duration of the study. for the purpose of this study, adequate contraception is defined as: * oral, injected or implanted hormonal methods of contraception; or * placement of an intrauterine device (iud) or intrauterine system (ius); or * barrier methods of contraception: condom or occlusive cap (diaphragm or cervical/vault caps) with spermicidal foam/gel/film/cream/suppository note: male sterilisation or abstinence are not acceptable methods of birth control and would preclude enrolment in the study. note: for post-menopausal women: less than 12 months since the last spontaneous menstrual bleeding will exclude the patient unless they are willing to utilise acceptable methods of contraception for the duration of the study. * male subjects able to conceive, who are unwilling to use barrier methods of contraception throughout the duration of the study * subjects unable to comply with the study assessments.

Keywords: osteoarthritis pain knee