DI-032 Study of effectiveness and safety of foscarnet in cytomegalovirus treatment in haematopoietic stem cell transplantation recipients

Background Cytomegalovirus disease is an important cause of morbidity and mortality in haematopoietic stem cell transplantation (HSCT) recipients. Foscarnet, an intravenous drug active against cytomegalovirus, represents an increasingly widespread alternative when there is resistance or intolerance to conventional treatments (ganciclovir/valganciclovir, acyclovir). More data about its use, effectiveness and safety in the clinical practice are necessary. Purpose To analyse the effectiveness and safety of the use of foscarnet against cytomegalovirus in HSCT recipients, and its adaptation to clinical practice guidelines and expert recommendations in order to optimise future treatment strategies. Material and methods Observational, retrospective, single centre study including all adult HSCT recipients treated with foscarnet for pre-emptive therapy or treatment of cytomegalovirus in a tertiary hospital between January 2013 and June 2015. Demographic, effectiveness and safety data about the treatment were collected and analysed using Access and Excel. After a literature search, results were compared with clinical trials and retrospective studies published, as well as with clinical practice guidelines and expert recommendations. Results 43 episodes in 34 patients were included (50% women) with a median age of 52 years (range 47–57). In 9 cases (31%) of pre-emptive therapy, no patient experienced reactivation of cytomegalovirus. In 34 cases of treatment after reactivation, 85.7% (n = 29) started with a positive cytomegalovirus viral load. Of them, 72.4% reach negative viral load, 20.7% died and 6.9% were considered resistant. The remaining 14.3% (n = 5) maintained negative for viral load during treatment. All patients experienced at least one adverse effect but only 3% discontinued treatment. There were electrolytic disorders (100%), creatinine alterations (32.6%) and gastrointestinal disturbances (9%). Concomitant drugs causing electrolyte alterations or renal toxicity were not registered. Conclusion Foscarnet was shown to be effective with acceptable toxicity in cytomegalovirus treatment in HSCT recipients. The results are not entirely comparable with other published studies 1,2 due to differences between populations and therapeutic regimens. The use of foscarnet (indications, dosage and treatment duration) in hospital mainly follows recommendations of experts and guidelines. More studies should be carried out in order to get the most beneficial treatment regimen with the minimum adverse effects. References and/or Acknowledgements Reusser P, et al . Randomised multicenter trial of foscarnet versus ganciclovir for preemptive therapy of cytomegalovirus infection after allogeneic stem cell transplantation. Blood 2002;99:1159–64 Asakura M, et al . Use of foscarnet for cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation from a related donor. Int J Hematol 2010;92:351–9 No conflict of interest.