A quarter of United Kingdom hospitals providing TB treatment had to interrupt a course of treatment due to drug supply problems in 2007 and 2008, according to results of a survey published this month in the International Journal of Tuberculosis and Lung Disease.
Although drug stock outs are commonly seen in less well-resourced settings, this is the first time that attention has been drawn to serious problems in the supply of TB drugs facing developed countries with strong drug supply systems.
“The UK is in a similar position to the 18% of countries surveyed by WHO who report an interrupted supply of first-line drugs.”
The survey, developed by the UK Coalition to Stop TB, an alliance of medical and non-governmental organisations, and by the All-Party Parliamentary Group on Global Tuberculosis, highlights problems in the consistent supply of both first-line and second-line drugs in the UK, and in the lack of suitable formulations for the treatment of TB in children.
The authors of the report call on the National Health Service Commercial Medicines Unit to take a leadership role to ensure consistent TB drug availability in the UK. They also say that pharmaceutical companies should be more proactive in informing hospitals of shortages of TB drugs. Pharmacists said that pharmaceutical companies had proved poor at keeping them informed about supply problems.
The survey was carried out in 2009, and sought responses from all clinical pharmacists and medical TB leads within National Health Service trusts in the United Kingdom. Responses were received from 77 of 168 NHS trusts in the UK (46%), representing approximately 60% of the UK burden of TB cases.
Sixty-three per cent of respondents had experienced difficulties in obtaining TB drugs in 2007 and 2008. Twenty of the 55 trusts which had treated cases of multi-drug resistant (MDR) TB reported difficulties in obtaining second-line TB drugs.
Twenty-one of 77 (27%) of respondents reported that difficulties in obtaining drugs had resulted in interruptions of TB therapy, and clinics treating MDR-TB had to interrupt treatment in 16% of cases due to supply problems.
Interruptions in drug supply resulted in changes to the TB treatment regimen in 15 of 77 clinics (19%).
Twenty-six per cent of clinics experienced problems in obtaining formulations of TB drugs suitable for children, resulting in the need to produce their own liquid formulations from crushed tablets. This process sometimes resulted in the use of differing strengths of TB medication being used with paediatric patients.
“It is hard to believe our findings could have no clinical consequences,” the authors say. Interruptions in treatment could lead to the development of drug resistance, or to a patient believing that their course of medication is either complete or that it can be interrupted without serious consequences. The majority of interruptions “occurred in MDR-TB patients where a change in prescribed medication could have a major impact on treatment response”, they point out.
“Our study suggests that the UK does not currently have an effective drug supply and management system and that it is at risk of creating home-grown drug resistance,” the authors conclude.
References
Capstick TGD et al. Treatment interruptions and inconsistent supply of anti-tuberculosis drugs in the United Kingdom. Int J Tuberc Lung Dis 15 (6): 754-760, 2011.