Tiludronate disodium

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Skelid (Sanofi Winthrop)
200 mg tablets

Indication: Paget's disease

Tiludronate adds to the choice of biphosphonates available for the treatment of Paget's disease. The biphosphonates work by inhibiting the resorption of bone.

In clinical trials, the effectiveness of tiludronate has been objectively assessed by measuring concentrations of serum alkaline phosphatase. This enzyme is increased in Paget's disease. A 3-month course of tiludronate will at least halve alkaline phosphatase in over half the patients. The concentration of alkaline phosphatase may remain reduced for up to 18 months. In some patients, the concentration will fall to the normal range. Some patients will experience a reduction in bone pain.

Tiludronate has been compared with etidronate in a company-sponsored trial of 234 patients. After 6 months, significantly more patients had responded to tiludronate than etidronate. However, neither drug had an advantage over the other in the reduction of bone pain.1

Only 6-7% of a dose of tiludronate is absorbed. As food reduces absorption, the tablets should not be taken less than two hours before or after a meal. Absorption is also reduced by calcium, so the tablets should be swallowed with water, not milk.

Tiludronate binds to bone. This means that it has a long half-life. The drug is gradually excreted unchanged in the urine.

The most frequent adverse effects are gastrointestinal, including abdominal pain, nausea and diarrhoea. Other adverse effects include asthenia, headaches and rashes. Bone mineralisation is not affected at therapeutic doses.