Off-label drug use in home palliative care: A non-evidence-based established practice.

Abstract

225 Background: Advanced cancer patients (pts) often present with multiple concomitant symptoms and off-label use of drugs (indications doses formulations administration route) is a common practice. Drugs mixture (DM) solutions by continuous administration are frequently used. However, evidence-based data in this setting is scarce. Methods: We performed a retrospective analysis of 576 consecutive care pathways provided by our Home Palliative Care (HC) Service from Jul 2010 to Jun 2017. Infusions were administered subcutaneously (sc) or by a venous (iv) access, by elastomeric pumps (EP) (5 days - 2 mL/h) with drugs diluted in 0.9% NaCl with no light protection. We analyzed: treated symptoms, drugs, doses/concentrations, solution transparency, administration route, infusion duration, clinical response, adverse events (AEs), compliance/treatment acceptability, device proper functioning, and treatment interruptions. Results: We analyzed 266 pts out of 576 care pathways treated with DM infusions, M/F 143/123, median age 70 yrs (21-92); treated symptoms: pain (50%), nausea/vomiting (20%), dyspnea/agitation (20%), dysphagia/mucositis (18%); infused drugs: morphine, midazolam, dexamethasone, ranitidine, metoclopramide, scopolamine, alizapride, haloperidol, furosemide, and ketorolac. Median number of drugs in the DM was 3 (1-6). Administration route was sc in 214 pts/80%, iv in 52 pts/20%. Median infusion duration was 5 days (0-64). Symptoms control was achieved within 72 h in 69% of pts. No AEs related to the infusion devices were observed. Compliance was good in 92% of pts, poor/inadequate in 8%. 5 EP malfunctions were observed: 1 human error, 1 device obstruction due to furosemide flocculation, 3 unexplained. Also, 3 pts required sc infusion interruption due to fluid accumulation near the injection site. Conclusions: This retrospective analysis on a large number of pts shows efficacy and tolerability of DM administration by EP in the HC setting. Treatment compliance was high, no AEs were observed, EP malfunction and therapy discontinuation were rare. However, there are still many open questions about the off-label use of drugs in this setting, and prospective trials are strongly suggested.