I bet you’ve been wondering, where you been girl? Well I’m back! New job, new look and New Year!
The above title refers to a FDA (Food and Drug Administration) Alert I received yesterday (January 4, 2016). Posaconazole or Noxafil® is used to prevent certain invasive Aspergillus and Candida fungal infections in patients 13 years or older, who have weakened immune systems.
The reason for the alert is that prescribing errors have occurred where the oral sustained released tablet have been dispensed (or substituted) for the oral suspension. These two formulations are not equivalent mg for mg. If a patient has been dosed on the oral suspension you cannot change him/her to the oral sustained released tablet (this would account for an increase) and vice versa – if a patient has been on the oral sustained release tablet, you cannot substitute the oral suspension mg for mg (this would account for a decrease in dosage).
The FDA warned that there have been 10 cases where the posaconazole doses were too high because patients switched from the oral suspension to the tablet without a dose and frequency adjustment. Some of these patients experienced nausea and vomiting and one patient experienced a low serum potassium level. The most serious case was a patient taking the oral sustained release tablet to prevent invasive Aspergillus and Candida infections died of a stroke related to an Aspergillus infection after a pharmacist substituted the oral suspension at the same dose and frequency without realizing it amounted to an under dose. There is more information on the FDA Website.
Going forward best practices warrants that prescribers should specify the dosage form, strength and frequency on all prescriptions for Noxafil®. Pharmacists should clarify all prescriptions for Noxafil® if no dosage form is present. Pharmacists should also remind prescribers that Noxafil® sustained released oral tablets are not equivalent to Noxafil® oral suspension.
Merck does provide assistance for patients on Noxafil®. A 3 ½ ounce bottle of the suspension can run in excess of $1300.00. Providers who wish to prescribe Noxafil® for their patients can direct them to Merck’s website. Patients can enroll in Merck’s ACT Program online or contact ACT at 866.363.6379 between the hours of 8:00 a.m. – 8:00 p.m. EST. Patients will have to meet the eligibility requirements of uninsured or underinsured, those with Medicare Part D can enroll, income must be at or below 500% of FPL (Federal Poverty Level) and you must be a US Resident being treated by a US licensed healthcare provider.