Although ~27% UK OA population (~1.8m) take drugs to relieve pain, neither oral nor topical NSAIDs alleviate all moderate/severe symptoms and opiates are inappropriate for long-term use. Agents that relieve pain rarely have structure modification benefits; in some cases they’re detrimental to the joint.
27 million Americans of all ages suffer from osteoarthritis with many progressing to joint replacement surgery. Osteoarthritis accounts for 55% of all arthritis related hospital admissions (632,000 in 2004, an increase of over 50% in less than 10 years). In the USA, in addition to drug – drug interactions, renal, cardiovascular and GI adverse events related to NSAID use are likely to exceed $4 billion.
Indirect costs include those costs associated with loss of productivity, absenteeism, premature mortality and disability payments/benefits. In the USA it has been estimated that the cost of absenteeism alone exceeds $10 billion.
Adverse events and increasing concern for drug-drug interactions means that the next generation of OA treatments will likely need to demonstrate long term safety and minimal drug interactions, increasing typical time-to-market and reducing market attractiveness to developers.