Open-label Extension Study Of RN624

AE: any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. SAE: an AE resulting in any of following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent are events between first dose of study drug and up to 12 weeks after last dose that were absent before treatment in this study or that worsened relative to pretreatment state. AEs included both SAEs and non-serious adverse events.

The WOMAC pain subscale is a 5-item questionnaire used to assess the amount of pain experienced due to osteoarthritis in index knee during past 48 hours. It is calculated as mean of the scores from the five individual questions scored on a visual analog scale (VAS) of 0 to 100, where higher scores indicate higher pain. Total score range for WOMAC pain subscale score is 0 to 100, where higher scores indicate higher pain.

The WOMAC stiffness subscale is a 2-item questionnaire used to assess the amount of stiffness experienced due to osteoarthritis in index joint during past 48 hours. It is calculated as mean of the scores from the 2 individual questions scored on VAS of 0 to 100, where higher scores indicate worse function. Total score range for WOMAC stiffness subscale score is 0 to 100, where higher scores indicate worse function. Stiffness is defined as a sensation of decreased ease in movement of knee.

The WOMAC physical function subscale is a 17-item questionnaire used to assess the degree of difficulty experienced due to osteoarthritis in index joint during past 48 hours. It is calculated as the mean of the scores from the 17 individual questions scored on VAS of 0 to 100, where higher scores indicate worse function. Total score range for WOMAC physical function subscale score is 0 to 100, where higher scores indicate worse function.

Participants answered: "In the past 24 hours, how much pain have you had in your index knee caused by your osteoarthritis?" Participants responded by using a VAS of 0 to 100, where 0 = no pain and 100 = extreme pain, higher scores indicated more pain.

Participants answered: "Considering all the ways your arthritis affects you, how are you feeling today?" Participants responded by using a VAS of 0 to 100, where 0 = very poor and 100 = very good, where higher scores indicated better health condition.

Participants answered: "Overall, how satisfied are you with the study drug treatment you received as part of this study?" Participants responded by selecting the most appropriate among the following responses: not at all satisfied, a little satisfied, somewhat satisfied, and very satisfied.

SF-36 is a standardized survey evaluating 8 aspects of functional health and well-being: physical and social functioning, physical and emotional role limitations, bodily pain, general health, vitality, mental health. These 8 aspects can also be summarized as physical and mental component scores (CS). The total score for each section and 2 component scores are an average of the individual question scores, which are scaled from 0 to 100, where 0=lowest level of functioning and 100=highest level of functioning, higher scores indicated better functioning .

Median time of participation in the study for all the participants was evaluated.

HVLT-R: instrument consisting of 12 noun list, used to measure verbal learning and memory (recognition and recall). List was read to participant, who then attempted to recall as many words as possible. The examiner recorded each response. Task was repeated 2 more times, for total of 3 learning trials. After delay interval of 20-25 minutes, delayed recall trial was administered. Total score (TS) = sum of 3 learning trial scores of 12 word each, ranged: 0 (no memory) to 36 (best memory), where higher scores indicated better memory. Delayed recall (DR) = number of words recalled in delayed recall test, ranged: 0 (no memory) to 12 (best memory), where higher scores indicated better memory.