A New Validated Stability indicating RP-HPLC Method for Simultaneous Quantification of Impurities of Fluticasone Propionate and Salmeterol Xenafoate in Metered Dose Inhalation Aerosol

A simple, specific, precise, accurate and stability indicating reversed phase HPLC method for simultaneous quantification of total 12 impurities of fluticasone propionate and salmeterol xenafoate in metered dose inhalation aerosol has been developed in the present work. Chromatographic separation between impurities of both compounds were achieved on Altima C18 250 × 4.6 mm, 5 μ column using a step-gradient elution at a flow rate of 1.4 mL/min, 0.1% v/v orthophosphoric acid as buffer and acetonitrile as mobile phase constituents. Forced degradation studies for drug product were performed and revealed that Salmeterol is acid sensitive (about 21.3%), degrades to IMP-D and fluticasone is alkali sensitive (about 7.6%) and degrades to IMP-A. All degradant and process related impurities of both compounds were monitored at 214 nm and spectral purity along with % mass balance is assessed using PDA detector, which proved stability indicating capability of the method. The developed method is fully validated as per current ICH guidelines, where precision is achieved at % RSD of < 5, Correlation of < 0.999 for linearity, LOD-LOQ at < 0.02% and < 0.05%, along with satisfactory system suitability results under robustness conditions.

A New Validated Stability Indicating RP-HPLC Method for Simultaneous Quantification of Formoterol Fumarate Dihydrate and Mometasone Furoate in Metered Dose Inhalation Aerosol

Stability indicating reversed phase-HPLC method for simultaneous estimation of mometasone furoate (MAF) and formoterol fumarate (FFD) in metered dose inhalation aerosol (MDI) dosage formulation has been developed and discussed in the present work. The chromatographic separation was achieved using Hypersil ODS column (250 mm × 4.6 mm, 3 μm) using an isocratic separation mode at a flow rate of 1.2 mL/min, column temperature of 50 ºC. The system operates with a mobile phase comprising of solution-A (buffer): Solution-B (acetonitrile) mixed in the ratio of 70:30 %v/v at a UV detection wavelength of 214 nm. Retention times of mometasone furoate and formoterol fumarate found to be about 3 min and 7 min, respectively. All possible degradation products of both compounds were monitored at 214 nm and spectral purity along with % mass balance is assessed using PDA detector. Both analyte were subjected to force degradation studies, found all degradants were resolved from analyte peaks and also other process-related impurities. The proposed method is validated for specificity, linearity, accuracy, precision and robustness as per ICH guidelines and found to be adequate. Method stood to be robust with variation in column temperature, flow rate, pH of buffer and organic content in mobile phase.

Trans-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzz-E) (2018)

Trans-1,1,1,4,4,4-hexafluoro-2-butene (HFO-133mzz-E) is an odorless gas that finds uses as a foam transfer agent, heat transfer fluid, and specialty gas. The acute 4-h LC50 (in rats) for HFO-133mzz-E is > 17,000 ppm; it was not an eye or dermal irritant in 3- and 13-week repeated-dose inhalation studies in rats at concentrations up to 1.5% (15,000 ppm). HFO-133mzz-E was not a cardiac sensitizer at 70,000 ppm in a standard epinephrine challenge study in Beagle dogs. In a 3-week, repeated-dose (non-GLP) inhalation range-finding study in male and female rats, HFO-133mzz-E concentrations of 7500 and 15,000 ppm were determined to be well-tolerated. In the follow-up, GLP-compliant, 28-day repeated-dose inhalation study (as per OECD 412), male and female rats were exposed to 0, 1000, 10,000, or 15,000/20,000 ppm (20,000 ppm concentration was decreased to 15,000 ppm after week 1 because of deaths and body weight loss). The study no-observed-adverse-effect level (NOAEL) was established at 10,000 ppm based on reduced body weight gain and mortality observed at 15,000 ppm. In a 90-day GLP-compliant repeated-dose study (as per OECD 413), male and female rats were exposed to 0, 1000, 5000, 7500, or 15,000 ppm HFO-133mzz-E. Three male rats exposed to 15,000 ppm HFO-133mzz-E died during exposure; clinical signs such as restlessness, blepharospasm, and myoclonic jerks were also observed, during the first month of the study, at 15,000 ppm. There were no significant gross or histopathological organ/tissue lesions attributable to HFO-133mzz-E exposure. The study NOAEL was established at 7500 ppm. In a GLP prenatal developmental study (OECD 414), groups of time-mated nulliparous female rats were exposed via inhalation to 0, 1000, 5000, 7500, or 15,000 ppm HFO-1336mzz-E beginning on gestation day (GD) 6 up to and including GD 19. Under the conditions of this study, the NOAEL for maternal and fetal effects was established at 7500 ppm. HFO-1336mzz-E was not genotoxic in either in vitro or in vivo assays. Based on the results of the 90-day inhalation study, 7500 ppm was determined to be the NOAEL and was selected as the point of departure for the derivation of the 8-h time-weighted average (TWA), health-based workplace environmental exposure level (WEEL) value. This subchronic inhalation NOAEL was adjusted to account for duration of exposure, interindividual variability, and intraindividual variability. The resulting 8-h TWA WEEL value of 400 ppm is fully expected to provide a significant margin of safety against the production of any potential adverse health effects in workers following long-term inhalation exposure to HFO-1336mzz-E.

1,1,1,3,3,3-Hexamethyldisilazane (2018)

1,1,1,3,3,3-Hexamethyldisilazane (HMDZ) is used industrially to treat the surface of silica, as an intermediate adhesion promoter or silylating agent in the semiconductor industry, as a chemical modifier of inorganic fillers, and as a water scavenger silicone sealant. In animal studies, HMDZ is considered to be slightly to at most moderately toxic following acute administration via oral, dermal, and inhalation routes of exposure. HMDZ is neither an eye irritant nor was it dermally irritating under semiocclusive conditions; however, it caused dermal necrosis in two studies under occlusive conditions. HDMZ is not genotoxic or mutagenic in in vitro assays and was not reproductively or developmentally toxic in an inhalation screening study in rats. Short-term and subacute, high-dose inhalation exposure to HMDZ produced respiratory tract irritation, reduced feed consumption, changes in clinical chemistry parameters, and reversible central nervous system depression in rats. In a 90-day inhalation exposure study in rats, HMDZ exposure-related effects were observed in the kidneys of male rats but were determined to be alpha-2µ-nephropathy, thus, not relevant to humans. Based on the results of the 90-day (subchronic) inhalation study, 75 ppm was determined to be the no-observed adverse effect level (NOAEL) and was selected as the point of departure for the derivation of the 8-h time-weighted average (TWA), health-based workplace environmental exposure level (WEEL) value. This subchronic inhalation NOAEL was adjusted to account for duration of exposure, interindividual variability, and intraindividual variability. The resulting 8-h TWA WEEL value of 10 ppm is fully expected to provide a significant margin of safety against any potential adverse health effects in workers following long-term inhalation exposure to HMDZ vapor. A 15-min short-term exposure limit of 50 ppm was also established to protect workers from reversible effects produced by acute, high-dose inhalation of HMDZ vapor. A skin notation (Skin) is warranted because of the potential for the dermal route to significantly contribute to the overall exposure to HMDZ.