Revision of the South African genus Chasmanthe (Iridaceae)

The genus Chasmanthe, which is closely related to Tritonia and Crocosmia, is indigenous to the Cape Province of the Republic of South Africa. Out of the nine species established by N.E. Brown in 1932 only three, namely C. aethiopica (L.) N.E. Br., C. floribunda (Salisb.) N.E. Br. and C. bicolor (Ten.) N.E. Br., are accepted. Four species have already been transferred to other genera and two are now reduced to synonymy. C. aethiopica and C. floribunda are abundant in the southern and south-western Cape Province, the former being found as far as the Transkeian border in the eastern Cape Province. C. bicolor is rare and has a limited distribution in a few south-western Cape districts. All are adapted to winter rainfall conditions, sprouting in autumn and flowering in spring.S. Afr. J. Bot. 1985, 51: 253–26

Biowaiver Monographs for Immediate Release Solid Oral Dosage Forms: Proguanil Hydrochloride.

Literature data relevant to the decision to waive in vivo bioequivalence testing for the approval of generic immediate release solid oral dosage forms of proguanil hydrochloride are reviewed. To clarify the Biopharmaceutics Classification System (BCS) classification, experimental solubility and dissolution studies were also carried out. The antimalarial proguanil hydrochloride, effective via the parent compound proguanil and the metabolite cycloguanil, is not considered to be a narrow therapeutic index drug. Proguanil hydrochloride salt was shown to be highly soluble according to the FDA, WHO and EMA guidelines, but data for permeability are inconclusive. Therefore, proguanil hydrochloride is conservatively classified as a BCS Class 3 substance. In view of this information and the assessment of risks associated with a false positive decision, a BCS-based biowaiver approval procedure can be recommended for orally administered solid IR products containing proguanil hydrochloride, provided well-known excipients are used in usual amounts and provided the in vitro dissolution of the test and reference products is very rapid (85% or more are dissolved in 15 minutes at pH 1.2, 4.5 and 6.8) and is performed according to the current requirements for BCS-based biowaivers

Biowaiver Monograph for Immediate-Release Solid Oral Dosage Forms: Ondansetron.

Literature data pertaining to the physicochemical, pharmaceutical, and pharmacokinetic properties of ondansetron hydrochloride dihydrate are reviewed to arrive at a decision on whether a marketing authorization of an immediate release (IR) solid oral dosage form can be approved based on a Biopharmaceutics Classification System (BCS)-based biowaiver. Ondansetron, a 5HT3 receptor antagonist, is used at doses ranging from 4 mg to 24 mg in the management of nausea and vomiting associated with chemotherapy, radiotherapy, and postoperative treatment. It is a weak base and thus exhibits pH-dependent solubility. However, it is able to meet the criteria of "high solubility" as well as "high permeability" and can therefore be classified as a BCS class I drug. Furthermore, ondansetron hydrochloride 8 mg IR tablets (Zofran® 8 mg) and multiples thereof (16 mg = Zofran® 8 mg × 2 tablets and 24 mg = Zofran® 8 mg × 3 tablets) meet the criteria of "rapidly dissolving" in dissolution testing. Ondansetron hydrochloride has a wide therapeutic window and is well-tolerated after oral administration. Based on its favorable physicochemical properties, pharmacokinetic data and the minimal risks associated with an incorrect bioequivalence decision, the BCS-based biowaiver procedure can be recommended for ondansetron hydrochloride dihydrate IR tablets