Correlation between dispensed and prescribed doses of factor products for bleeding disorders: can a small,...

The prescribing and dispensing of factor replacement products have come under scrutiny in recent years. Some payers are shunting patients away from local 340B pharmacies anticipating larger pharmacies will be better able to match dispensed antihaemophilic factor vials to the prescribed dose. Our aims were to assess our baseline ability to achieve an aggregate and per patient dispensed to prescribed factor ratio (D:P ratio) of 1 and to evaluate obstacles to achieving unity. We conducted a retrospective review of the factor products dispensed from our 340B pharmacy and the corresponding prescriptions over the 6-month period prior to instituting routine D:P ratio assessment. The mean D:P ratio for all 65 patients was 1.00 (SD = 0.07). The mean paediatric D:P ratio differed from unity (P = 0.017) and from the mean adult D:P ratio (P = 0.003) in favour of a higher dispensed dose. A correlation between lighter patients and a higher dispensed dose was observed. Also, paediatric patients receiving 2 vials per dose had a mean D:P ratio greater than unity (P = 0.002). Pharmacy size does not dictate the ability to achieve a D:P ratio of unity. Ongoing monitoring of D:P ratios and dose ranges prescribed should be performed by all pharmacies to ensure acceptable allocation and cost of factor replacement for each patient. To further improve the D:P ratio metric in the paediatric population manufacturers should strongly consider adding more nominal dose increments within their lower range of vial sizes.