CO-64 | REAPPRAISAL OF DESMOPRESSIN FOR MANAGEMENT OF MILD/MODERATE VON WILLEBRAND DISEASE: RESULTS OF A RETROSPECTIVE ANALYSIS IN 127 ITALIAN PATIENTS SUGGEST FURTHER ORGANIZATION OF PROSPECTIVE OBSERVATIONAL STUDIES TO PREDICT DESMOPRESSIN FAILURE WITH IMMEDIATE VWF CONCENTRATES REQUIREMENT

A.B. Federici¹, G. Castaman² | ¹Ematologia e Medicina Trasfusionale, Ospedale Luigi Sacco, Polo Didattico Università di Milano, Italy; ²Centro Emofilia e Malattie Emorragiche Regione Toscana, Ospedale Careggi, Firenze, Italy

Background. Desmopressin (DDAVP) has always been considered the treatment of choice for patients with mild/moderate von Willebrand disease (VWD), but no standardized criteria have been reported so far to predict the benefits/limits of DDAVP in the management of a very large cohort of VWD.
Aims. To establish correct indications of DDAVP, we have recently re-analyzed clinical data of patients who received DDAVP treatment at two Italian centers during the last 15 years (2010-2025).
Methods. The following criteria were required to include cases in this retrospective analysis: age >12 years, bleeding score >5 by BAT, 10-40 U/dL of platelet-derived VWF activity (PD-VWF:ACT) and/or VWF collagen binding assay (VWF:CB), and a trial to determine biological response with assessment of PD-VWF:ACT, VWF:CB, FVIII:C, and VWF:AG at baseline and 1-2 hours following DDAVP. Exclusion criteria were known cases with VWD3 and VWD2B, children <12 years, absence or uncompleted data of trial, and no patient consent to retrieve their clinical data. DDAVP was given either by subcutaneous injections or intravenously during minor/major surgeries. Efficacy/safety of DDAVP was assessed by statistics after retrieving data from patients' charts into EXCEL files. DDAVP failure was defined when VWF-C was required. Side effects were also registered.
Results: among 153 cases, 127 (83%) met inclusion criteria as VWD1 (n=78), VWD1C (n=16), VWD2A (n=15), and VWD2M (n=18). Biological response was complete, partial, and absent in 75%, 23%, and 2%. These 127 VWD received DDAVP for bleeds (n=104), oral surgeries (n=33), deliveries (n=12), and minor/major surgeries (n=25). Total injections were 652 with median and range/episode during bleeds (2.1-12), oral surgeries (1.1-10), deliveries (3.1-13), and minor/major surgeries (3.6-16). Efficacy was excellent/good in bleeding (83%), oral surgery (100%), deliveries (87%), and minor/major surgeries (82%). Failure was found in VWD1C, who required VWF-C after a caesarean section, and in 5/25 minor/major surgeries [abdominal (n=2), hysterectomy (n=1), tonsillectomy (n=1), orthopedic (n=1)] in VWD2A and VWD1. Side effects (n=16) were mainly minor (flushing, headache, tachycardia), with 2 cases of water retention reported (>12 doses).
Conclusions. DDAVP should always be recommended as first-line therapy in responsive mild/moderate VWD patients in bleeding episodes, oral surgery, deliveries, and major surgeries. Prospective clinical observations, as those recently proposed by European investigators, are required to predict DDAVP failure with immediate indication of VWF-C.