The fixed dose combination of ledipasvir (LDV) and sofosbuvir (SBV) is approved by USFDA in 2014 for the treatment of Hepatitis C virus infection and is available in the form of tablets. In the present work, the principal aim is to explore orodispersible films type dosage form to impart its characteristic advantages to these poorly soluble drugs so as to improve their bioavailability and ease of administration. Solid dispersions with low viscosity grade methyl cellulose A 15-LV (MC A 15-LV) at different ratios with LDV and SBV were prepared and evaluated to check their ability in improving the solubility of the drugs. The best drug to polymer ratio was selected to develop the films, using other excipients including plasticizer and superdisintegrant. Solvent casting method was used to develop the films. Three formulation parameters were selected as independent factors viz. thickness of the film (50-150 µm), concentration of superdisintegrant (sodium starch glycolate 6-10%) and concentration of plasticizer (polyethylene glycol 400, 10-20%). Disintegration time (DT), time for 90% dissolution (T90%) of LDV and time for 90% dissolution of SBV were taken as the response variables. The experiment was designed using Box-Behnken design. Among the polymers, MC A 15-LV produced maximum solubility at 1:2 ratio. The films obtained were found to have good tensile strength and % elongation with disintegration times in the range of 43-162 sec. The T90% values for LDV and SDV were found to be in the range of 8.4-21.2 min and 7.2-18.4 respectively. All the three formulation factors were found to have significant effect on the three responses. The optimum formulation was identified at 100 µm thickness, 10% superdisintegrant and 20% plasticizer which showed DT of 89 sec with T90% values of 8.4 min and 7.2 min for LDV and SBV respectively. The rapid disintegration and dissolution of the films signified that the set objective was achieved.

Background: Fast-dissolving tablets (FDTs) were aimed to be developed for the latest approved combination drugs for Hepatitis-C treatment, Ledipasvir (LDV) and sofosbuvir (SBV) which suffered with poor water solubility. Materials and Methods: Cyclodextrin (CD) complexation was done for the drugs to improve their solubility. The optimized CD complexes were taken for developing FDTs to improve dissolution limited bioavailability of these drugs. FDTs were developed by adopting design of experiments approach using Design Expert software. Type of β-CD, type of disintegrant and concentration of disintegrant were taken as the factors. Disintegration time, time for 90% dissolution of LDV and SBV were taken as the responses. The prepared tablets as per the selected experimental design were evaluated for the responses and also other characteristics like tensile strength, packing fraction, wettability. The results were analyzed by ANOVA and numerical optimization was performed with the desirability of minimizing all the responses. Results: All the selected factors were found to influence disintegration and dissolution times significantly. Dimethyl β-CD, croscarmellose sodium at 8% w/w was obtained as the optimized combination of the factors for the FDTs. The FTDs at this optimized combination of the factors were found to have 79.6 sec of DT, 17.72 and 13.68 min. of time for 90% dissolution of LDV and SBV respectively. Conclusion: These results which were significantly much better than those of the marketed tablets indicated that the FTDs were successfully developed using Design of experiments.

Ledipasvir (LDV) and sofosbuvir (SBV) are poorly soluble drugs and hence dissolution limited bioavailability is a major concern. Further, the high total dose of this combination (LDV-90mg and SBV-400mg) may cause swallowing difficulties if formulated into tablets. Considering these challenges, it was aimed in the current research work to develop orodispersible films (ODFs) for this combination to enhance dissolution thereby bioavailability and also patient convenience. ODFs, because of their ready dispersibility in the oral cavity dissolution would be rapid and also high doses of drugs can be incorporated avoiding swallowing difficulties. HPMC E15 was taken as the film former. Thickness of the films (50µm – 150µm), concentration of superdisintegrant (sodium starch glycolate 6-12% w/w) and concentration of plasticizer (polyethylene glycol 400, 10-20% w/w) were taken as three formulation factors each at three levels. Using Design Expert software, Box-Behnken design under response surface methodology was selected as the experimental design. Disintegration time (DT), time for 90% dissolution of LDV (LDV-T90%) and time for 90% dissolution of SBV (SBV-T90%) of the ODFs were taken as response. The films were developed using solvent casting method. The obtained films were subjected for various quality characteristic studies like differential scanning calorimetry, X-ray diffraction, tensile strength, % elongation, folding endurance, disintegration time, drug content uniformity and dissolution studies. All the formulations were found to have favorable tensile strength, % elongation and folding endurance. The DT values were found to be in the range of 37 – 139 sec.; the values of LDV-T90% and SBV-T90% were found to be in the range of 7.1 – 20.7 min. and 6.8 – 15.6 min. respectively. The results of these three responses were subjected to ANOVA studies and found that all the three formulation factors were having significant effect. The results of optimization by desirability functions approach indicated the ODFs with thickness 50µm, disintegrant at 12% w/w and plasticizer at 17.46%w/w as the optimized formulation. The ODFs prepared at this combination showed DT of 45 sec, LDV-T90% of 7.51 min. and SBV-T90% of 6.23 min. these results indicated that ODFs for LDV and SBV were successfully optimized and developed.