Johnson & Johnson and marketing partner Schering-Plough are celebrating the news that regulators in the USA have given the green light to the arthritis drug Simponi, which has been touted as a potential blockbuster.

The US Food and Drug Administration has approved Simponi (golimumab) for three rheumatic indications – the treatment of moderate to severe rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis. Specifically, it is intended for use in combination with methotrexate in patients with RA, with or without methotrexate for psoriatic arthritis and alone in patients with AS, which can result in the fusing of the spinal vertebrae and cause structural damage to hips and other joints.

The once-monthly subcutaneous injection human monoclonal antibody that is an anti-tumour necrosis factor therapy like Amgen/Wyeth’s Enbrel (etanercept), which needs to be injected every week and Abbott’s every-other-week jab Humira (adalimumab). J&J and S-P already market Remicade (infliximab), which is administered by intravenous infusion every eight weeks.

The approval is based on data from more than 2,000 patients across five Phase III trials. Kim Taylor, president of J&J’s Centocor Ortho Biotech unit, noted that the firm has collaborated with the FDA to develop a risk evaluation and mitigation strategy “to help ensure the risks of anti-TNF therapy are appropriately managed".

Like other drugs in the class, the label on Simponi includes a boxed warning alerting patients and healthcare professionals to the risk of tuberculosis and serious fungal infections.

Simponi, which was approved in Canada last week, and J&J has exclusive marketing rights to the product in the USA. Following other approvals, S-P will sell it elsewhere except in Japan, Indonesia and Taiwan, where it will be co-marketed by Mitsubishi Tanabe Pharma Corp and Janssen Pharmaceutical Kabushiki Kaisha. In Hong Kong and China, Simponi will be sold by Janssen-Cilag and Xian-Janssen, respectively.

Analysts have estimated that the biologic could have sales of $3 billion in the next three years and glimumab is thought to be one of the main reasons why Merck & Co is acquiring S-P for $44.5 million. That deal has been structured as a reverse merger in a bid to avoid change-of-control provisions in S-P’s marketing agreement with J&J for Remicade and now Simponi.