Tolvaptan for ADPKD
The vasopressin receptor antagonist tolvaptan has been approved for use in Canada for the treatment of ADPKD. Given limited data, the medication is not indicated for all patients with ADPKD as only a subset of ADPKD patients may benefit. Based on its mechanism of action and the current studies available, patients most likely to benefit are those who are younger, with evidence of enlarged kidneys but preserved kidney function. Patients with slowly progressive disease who are not likely to reach ESRD are not likely to benefit from tolvaptan and the drug has not yet been studied in those with advanced renal dysfunction.
For information and suggestions regarding the
use of tolvaptan in ADPKD, please refer to the patient and prescriber FAQ
documents linked below. For more
detailed information on assessing renal prognosis in ADPKD and identifying
candidates for treatment, refer to the Canadian consensus recommendations on
ADPKD management found here.
Mandatory monitoring must be completed when using tolvaptan. A consent to drug use and hepatic monitoring are required, and bloodwork must be performed prior to each refill. Details of this process are outlined in the documents linked below, including the consent form, a request for bloodwork monitoring and a pre-printed prescription form.
To further enhance safety and outcome monitoring, we ask that all patients on tolvaptan be registered in PROMIS.
At this time, tolvaptan is not funded by either BC PharmaCare or the BC Renal Agency. Some private insurers have listed tolvaptan; we suggest that potential patients discuss this with their drug insurance provider prior to initiating treatment with tolvaptan. They should inquire about coverage as well as any lifetime maximums that may apply. Once a prescription is completed, the distributor will also ensure that funding is in place before dispensing tolvaptan. This may result in a delay of up to several weeks between prescribing and the first delivery of tolvaptan.