Biowaiver Monograph for Immediate-Release Dosage Forms: Levamisole Hydrochloride.

This work describes the potential applicability of the BCS-based Biowaiver to oral solid dosage forms containing Levamisole hydrochloride, an anthelmintic drug on the WHO List of Essential Medicines. Solubility and permeability data of levamisole hydrochloride were searched in the literature and/or measured experimentally. Levamisole hydrochloride is a highly soluble drug, but there is no clear evidence of high permeability in humans, indicating that it should provisionally be assigned to BCS class III. The biowaiver procedure would thus be applicable for solid oral dosage forms containing levamisole hydrochloride as the only active ingredient. Due to the lack of data in the literature regarding excipient effects on the bioequivalence of products containing levamisole, it is currently recommended that the products comply with the ICH and WHO guidelines: the test formulation should have the same qualitative composition as the comparator, contain very similar quantities of those excipients, and be very rapidly dissolving at pH 1.2, 4.5, and 6.8. However, for certain well-studied excipients, there appears to be opportunity for additional regulatory relief in future versions of the ICH BCS Guidance M9, such as not requiring that the quantities of these common excipients in the test and comparator be the same.

Development and evaluation of age-appropriate film-coated tablets of levamisole for paediatric use (2 - 18 years).

OBJECTIVES: To develop an oral solid dosage form of levamisole suitable for the paediatric population in terms of dose accuracy, palatability, stability and ease of administration. METHODS: Small undividable tablets (Ø5 - 8 mm) in four different strengths were manufactured to allow for flexible and accurate dosing. In vitro dissolution testing was used to determine drug release in different media. The bitter taste of levamisole was masked using a film-coat and assessed in healthy volunteers. Suitability and acceptability of the tablets were evaluated in 100 patients with nephrotic syndrome aged 2 - 18 years participating in a double blind, placebo-controlled, randomised trial. RESULTS: All tablet strengths showed good taste-masking characteristics and similar, pH independent, dissolution profiles. Successful taste masking was achieved without affecting the dissolution rate. In a total of 100 paediatric patients, more than 20,000 levamisole tablets were swallowed without any difficulties, choking or aspiration. CONCLUSION: The formulated tablets were found to be suitable for children aged 2 - 18 years and to provide good dose accuracy.