Letters to the Editor
- Aust Prescr 2012;35:39-42
- 1 April 2012
- DOI: 10.18773/austprescr.2012.018
The Editorial Executive Committee welcomes letters, which should be less than 250 words. Before a decision to publish is made, letters which refer to a published article may be sent to the author for a response. Any letter may be sent to an expert for comment. When letters are published, they are usually accompanied in the same issue by their responses or comments. The Committee screens out discourteous, inaccurate or libellous statements. The letters are sub-edited before publication. Authors are required to declare any conflicts of interest. The Committee's decision on publication is final.
Editor, – Shire Australia wishes to update the information about lanthanum carbonate that was published when the drug was new (New drugs, Aust Prescr 2006;29:54-5 ). Much has changed over the last six years and many more studies have been published, including long-term studies and a head-to-head comparison with sevelamer hydrochloride.
Given the current body of evidence, there appears no reason to suggest that lanthanum carbonate should not be used beyond two years. In fact, the Therapeutic Goods Administration considered the body of evidence in 2007 and made a decision to remove the two-year restriction. Treatment of patients for up to six years has not shown change in the harm–benefit profile.
Lanthanum carbonate is an effective binder of dietary phosphate for use in controlling the hyperphosphataemia of patients with chronic kidney disease on dialysis. Studies have shown that lanthanum carbonate can reliably be used to reduce serum phosphate concentrations and to effectively maintain control of serum phosphate during long-term use, up to six years.1,2 Maintenance of target phosphate concentrations has been shown to be similar between lanthanum, calcium phosphate binders1 and sevelamer hydrochloride.3
To date, 6297 patients have been exposed to lanthanum carbonate in Shire-sponsored clinical studies. In addition 5020 patients have been exposed for up to five years in two observational studies. Cumulatively the estimated worldwide patient exposure to lanthanum is 225 224 person-years treatment. The most commonly reported adverse drug reactions are headache, hypocalcaemia and gastrointestinal reactions (for example abdominal pain, diarrhoea, nausea and vomiting). Gastrointestinal reactions can be minimised by taking the tablets with food.
Results from long-term studies demonstrated that bone lanthanum concentration had no apparent effect on bone health (assessment has considered bone biopsy) or treatment outcome for up to 4.5 years.1 There are no clinical data examining the potential deposition of lanthanum in other tissues.