Abstract
Bucillamine is a disease modifying antirheumatic drug (DMARD), developed in Japan and widely used for more than 20 years. As the bucillamine molecule contains two SH radicals, it is unstable in the presence of water, causing an offensive smell or discolouration. Bucillamine went out of patent in 1988, and 6-generic products have been released in Japan. All the generic products have passed quality reevaluations by the Japanese Ministry of Health, Labour and Welfare, although no long-term stability testing has been conducted.
Sugimoto et al. conducted a 6 month accelerated stability trial of the original product and 4 generic products, finding decreased solubility and drug content in some of the generic products (Diagnosis and Treatment 2000; 88: 1940-3).
In this study, we conducted stability testing of 7 bucillamine preparations, comprising the original product and 6 generic products, in the final packaging, press through packing (PTP) and the unpackaged state, with the purpose of assessing the stability of these products up until they are taken by the patient. Our results showed that the original product and 2 of the generic products were stable under all conditions tested, but decreased solubility and drug content were seen in the remaining generic products. An unpleasant smell could be detected immediately upon removing the samples that had deteriorated over time from their packaging. Further quality evaluation using long-term storage studies are therefore required for these generic bucillamine preparations.
