Quality Assessment of Four Fixed Dose Combination Anti-tuberculosis Drugs in Government Facilities in Mombasa, Kilifi, Kwale and Nairobi Counties
The four fixed dose combination (FDC) anti-Tuberculosis (TB) drugs that the Kenyan government supplies through the National Leprosy and Tuberculosis Programme (NLTP) to the health facilities must be of high quality and effective in order to ensure success in TB treatment. According to Global Drug Facility (GDF), treatment of TB with poor quality anti-TB drugs could result in treatment failures as well as leading to drug resistance to Mycobacterium tuberculosis. It also has deleterious effects on the health of the wider population in Kenya. The NLTP is yet to achieve the internationally set targets of 85% cure rates of all detected TB cases. Although drugs have been registered by the Pharmacy and Poisons Board (PPB), under the Ministry of Health, their quality has not been regularly assured. The World Health Organization (WHO) estimates that up to 25% of drugs used in developed and developing countries are substandard. Therefore the main objective of the study was to assess the quality of anti-TB drugs supplied by NLTP to different levels of healthcare alongside internationally set standards in Mombasa, Kwale, Kilifi and Nairobi Counties and assess the storage conditions in the health facilities and in Kenya Medical Supplies Agency (KEMSA). The drugs were randomly sampled from eight health facilities in Nairobi, Mombasa, Kilifi and Kwale counties. Data on storage conditions was collected through a questionnaire administered at the time of collection of samples as well as through observation method. The drugs were analyzed for content, dissolution, uniformity of weight and friability in the National Quality Control Laboratory (NQCL). Results from the laboratory were entered in the computer and using the SPSS software version 11.5 was analyzed by descriptive statistics. The results indicated that uniformity of weight of all drugs sampled in all facilities complied with the specifications. Friability specifications for the drugs from seven facilities out of eight (87.5 %) complied. It is only the drugs from Diani health center that did not meet the specifications. Dissolution specification for Rifampicin was not met in 3 of 8 (37.5%) facilities. The specifications for dissolution of Isoniazid, Ethambutol, and Pyrazinamide were met in all the facilities. The assay of drugs for Rifampicin from 5 of the eight facilities (62.5%) was less than 90% thus failed to comply with the specification. Assay for Ethambutol was 112% which was outside the limits thus failed the test. Assay for the Isoniazid and Pyrazinamide from all the eight facilities complied. All samples from KEMSA and the Health Centers complied with specifications with regard to uniformity of weight and dissolution of Ethambutol, Isoniazid and Pyrazinamide as well as with respect to assays for Isoniazid and Pyrazinamide. For these tests, there was no difference on quality between drugs sampled from KEMSA and the Health Centers. Results from tests on friability and assays of Ethambutol indicated that one health facility out of eight (12.5%) failed to comply while samples from all KEMSA sites complied. There was better compliance of drugs from the Health Centers on dissolution and assay of Rifampicin than from KEMSA. Overall, drugs from all health facilities failed to comply with the specifications for various reasons. This study suggested that regular post market surveillance in all health facilities should be carried out as well as a regular storage facilities assessment.