Merck Sharpe Dohme have been promoting Montelukast (Singulair) recently specifically for patients with Asthma and Seasonal Allergic Rhinitis (SAR).
The promotion is supported by papers detailing the link between poorly controlled asthma and SAR - however the data in this paper were taken from the GP Practice database system a number of years ago and asthma care should have improved since then. In this paper more than half of the patients were not on a steroid inhaler for example.
As a consequence of this is seems more prudent to ensure that a patients asthma is well controlled before focussing on SAR symptoms, after all SAR is not a fatal disease. Asthma control should be attained by implementing and using the BTS Asthma Guidelines.
This view is support by a small study in children comparing Montelukast with inhaled Budesonide. In this study the efficacy of each therapy was assessed in terms of prevention of relapse was assessed following exposure to an allergen. The level of Bronchial Hyper-responsiveness to methacholine was unchanged in the Budesonide arm but rose significantly in the Montelukast arm.
Action: Patients with Asthma and SAR who suffer from poor asthma control while exposed to allergens should have their Asthma management optimised as per the BTS Asthma Guidelines before tackling SAR symptoms. This may involve Montelukast if the patient is at the appropriate BTS Step.
The Volumatic spacer device, which is intend for use with metered dose inhalers such as Ventolin and Becotide, is being discontinued and is unlikely to be available from the end of August 2005.
The Aerochamber Plus is going to be marketed in place of the Volumatic, however there are only limited data available to support the use of this spacer, with studies on-going to increase understanding of how this spacer affects drug deposition in the lungs.
Caution should therefore be used in changing the spacer device as changes in lung deposition could affect the side effect profile and efficacy of treatment. This may impact upon patient compliance with treatment and control of the underlying disease. Patients who are prescribed the replacement spacer device should be monitored carefully for side effects from treatment or for poor control of symptoms. Where loss of control of side effects occur, steps should be taken to alter the drug therapy to regain control of the disease without causing unnecessary harms.
Action: Prescribers should encourage patients to continue using their Volumatic spacers where possible until more data are available to support the Aerochamber Plus. When prescriptions are changed through necessity, the patients' condition should be monitored for loss of control or side effects.
Following the PCT recommendation to review prescribing of Atorvastatin 10mg and consider switching to Simvastatin 40mg, there have been several queries regarding the comparative tolerability of Simvastatin.
The CURVES Study1 compared the efficacy and tolerability of five statins, including Simvastatin and Atorvastatin. It found that "All reductase inhibitors studied had similar tolerability". This study is often quoted when comparing the relative efficacy of statins at differing strengths.
Similarly, the ASAP Study2 compared aggressive doses of Atorvastatin and Simvastatin (80mg vs 40mg) and found that "Both drugs were equally well tolerated".
Finally, the Heart Protection Study3 was a randomised, double blind trial that compared Simvastatin 40mg to placebo, with or without additional antioxidant vitamin supplementation. Over the period of the study (average 5 years) a third of patients in the Simvastatin arm and a third of patients in the placebo arm experienced muscle pain or weakness. Only 0.5% of these subsequenlty stopped the study medication (active or placebo).
Action: Clinical studies have shown that Simvastatin is equally well tolerated as other statins and the HPS Study has shown it is as well tolerated as placebo. Tolerability of Simvastatin should not be an issue when considering a switch from Atorvastatin 10mg to Simvastatin 40mg. Following the switch any patients do not tolerate Simvastatin can be switched back without problem.
- Jones P, et al. Comparative dose efficacy study of atorvastatin versus simvastatin, pravastatin, lovastatin, and fluvastatin in patients with hypercholesterolemia (the CURVES study). American Journal of Cardiology 1998; 81: 582-587.
- Smilde TJ, et al. Effect of aggressive versus conventional lipid lowering on atherosclerosis progression in familial hypercholesterolaemia (ASAP): a prospective, randomised, double-blind trial. Lancet 2001; 357: 577-581.
- Heart Protection Study Collaborative Group. MRC/BHF Heart Protection Study of cholesterol lowering with simvastatin in 20,536 high risk individuals: a randomised placebo-controlled trial. Lancet 2002; 360: 7-22M
The patent on Tamsulosin Capsules (Flomax) is due to expire in early 2006. The manufacturers are planning to release Flomaxtra XL tablets soon and a statement is expected. This product will contain the same drug at the same dose in a slightly different extended release presentation.
The manufacturers have gained agreement from the Scottish Medicines Consortium that Flomaxtra is acceptable for use as an alternative to Flomax capsules.
Action: Assuming that Flomax remains on the market up until the patent expiry, when generic versions become available, it should continue to be used.
Merck Sharpe & Dohme Ltd (MSD) have been asked to write to healthcare professionals to provide a corrective statement regarding their recent promotional activity of Fosamax 70mg Once Weekly (Alendronate).
The basis of the promotion had been that bioavailability (the rate and extent to which the drug is absorbed) is not the same between Fosamax and the recently released generic products. There was also an inferred link between this difference and the likelihood of side effects, specifically oesophageal injury.
In the corrective statement they point out that there is no link between incidence of oesophageal injury and bioavailability. Also, it should be noted that if there had been dramatic differences in bioavailability between Fosamax and the new generic products that product licenses would not have been granted to these new generic products.
Action: Prescribers should continue to prescribe Alendronate as generic where indicated. There is no reason to prescribe this product by brand.