Lymecycline

Hansen's disease or leprosy is a chronic, infectious disease that has locally and globally afflicted all populations. Despite standard treatment with multidrug therapy (WHO-MDT), the incidence of drug resistance has been an increasingly prevalent global problem in leprosy management. This study compared the effectiveness between lymecycline with WHO-MDT and standard WHO-MDT in leprosy treatment.

The research is a retrospective cohort study at a tertiary hospital from January 2011 to July 2021. Pre- and post-treatment bacillary index, presence of new lesions, nerve function impairment, and leprosy reactions were obtained through chart review.

The results showed a significant difference in bacteriological index (BI) in both groups at the end of the treatment. However, a higher reduction in BI was noted for the lymecycline group. For the group that took WHO-MDT alone, BI decreased by 0.7 (P < 0.001) whereas patients who took lymecycline and WHO-MDT had a BI difference of 3 (P < 0.001) upon completion of treatment. A significant decrease in the recurrence of lesions (P = 0.006) and nerve function impairment (P = 0.038) was also noted in the lymecycline group whereas there was no significant difference in leprosy reactions between the two groups.

Lymecycline 600 mg daily for 3 months can be used as an adjunct in cases of leprosy resistance and treatment failure among multibacillary patients. Lymecycline significantly reduced bacillary index, recurrence of skin lesions, and nerve function impairment through its possible immunomodulatory, antiapoptotic, and neuroprotective effects.

Tetralysal® is a Galderma oral drug product (DP) marketed for the treatment of acne. Tetralysal® is sold in capsules containing either 150 mg or 300 mg of the drug substance. In the British Pharmacopoeia monograph for Lymecycline Capsules, the impurities already specified in the drug substance (A-G), visible in the European Pharmacopoeia 〈1654〉, are also specified together with an unidentified impurity at RRT 1.6 (Impurity J). Based on both monographs Galderma has focused on characterizing most of specified and unspecified impurities to better understand the stability and degradation processes of the formulation. In this manuscript, through both formal synthesis, preparative LCMS and formal degradation studies, we are the first group to confirm the structural identities of 5 unidentified impurities (Impurity J (RRT 1.6), RRT 2.2, 2.4, 2.6 and 3.4), conditions which exacerbate the formation of all 5 impurities and response factors for RRT 2.2, 2.6 and 3.4.