In Vitro Assessment of Compounded Lurasidone Suspensions for Enteral Feeding Tubes

Purpose: Extemporaneously compounded drug suspensions are often necessary for patients who are intubated or receiving nutrition through enteral feeding tubes. Lurasidone is a relatively new antipsychotic medication available only as oral tablets (Latuda^®), and there is no data to support its use in this patient population as a compounded liquid formulation. This study was designed to assess the feasibility of preparing lurasidone suspensions from tablets and their compatibility with enteral feeding tubes. Methods: Representative nasogastric tubes were selected for this study, including polyurethane, polyvinylchloride, and silicone tubes with a range of 8 to 12 Fr (2.7-4.0 mm) in diameter and 35 to 55″ in length. Two strengths of lurasidone suspensions, 1 and 8 mg/mL, were prepared by the standard mortar-pestle method. Latuda^® tablet 120 mg was used as the drug source, and a 1:1 mixture of Ora-Plus^®:water was used as the suspension vehicle. The drug suspensions were delivered through the tubes mounted on a peg board to simulate patient position in a hospital bed. The ease of administration through the tubes was evaluated visually. The drug concentration before and after the tube delivery was analyzed by high performance liquid chromatography (HPLC). In addition, a 14-day stability study of the compounded suspensions was performed at room temperature to support the beyond-use dating. Results: Freshly prepared lurasidone suspensions, 1 and 8 mg/mL, met the potency and uniformity requirements. Both strengths of suspensions exhibited satisfactory flowability through all the tube types studied with no signs of clogging. The HPLC results confirmed that greater than 97% of drug concentration was retained after tube delivery. During the 14-day stability study, the suspensions retained greater than 93% of their original concentration. There was no significant change in pH or visual appearance. Conclusions: The study demonstrated a practical procedure to prepare 1 and 8 mg/mL lurasidone suspensions that are compatible with commonly used enteral feeding tube materials and dimensions. A beyond-use date of 14-day was established for the suspensions stored at room temperature.