At a time when some PCTs struggle to fund new drugs, a paper in the International Journal of Clinical Practice (2007;61:15-23) suggests that switching suitable patients from atorvastatin to generic simvastatin could save the NHS up to £1 billion without compromising outcomes. A similar switch from losartan to candesartan could save £128 million.

A team led by Usher-Smith, from Cambridge University, switched 70 and 111 patients taking atorvastatin and losartan respectively after careful screening using strict clinical criteria. They reviewed 122 patients taking atorvastatin and excluded 43 subjects. Seventy switched to simvastatin. One switched back to atorvastatin after experiencing visual symptoms. Clinicians excluded 26 of the 137 patients receiving losartan. A further six patients didn't want to switch. Seven switched back for a variety of reasons including: chest tightness; patient request; or anxiety about the antihypertensive treatment.

Four months after the switch, mean total cholesterol had not changed significantly. Patients who remained on candesartan showed a small, significant reduction in average blood pressure. No adverse events attributable to the switch emerged in either group. However, the switch could save considerable amounts.

An accompanying editorial (2007;61:2-3) notes that in 2004 English doctors prescribed a billion statin tablets, which accounted for 9% of the NHS drug budget. Prescribing rates are growing by 30% a year. Furthermore, more than 1.1 million people in England take atorvastatin 10 and 20 mg. Around 85% of patients take low or intermediate dose atorvastatin and simvastatin.

Usher-Smith and colleagues estimated that, including staff and administration costs, the practice saved £12,716 and £13,374 by switching statins and antihypertensives respectively. They suggest that savings will reach £14,713 and £14,009 respectively in future years. Atorvastatin’s patent expires in 2011 and over the next five years the practice would save £71,567. If the same proportion of patients switched across the PCT and nationally, the savings would be £2.4 million and £0.63 billion respectively. However, the study used conservative switch criteria. A 100% switch would translate into savings of £125,000, £4.2 million and £1.1 billion for the practice, PCT and UK, respectively.

Losartan’s and candesartan’s patents are due to expire in 2009 and 2012 respectively. So, in this case, savings would persist for the next three years. Switching >90% of patients to candesartan would translate into savings of £40 000, £0.41 million and £128 million in the practice, PCT and UK, respectively. By Mark Greener