Health technology assessment of new drugs for rare disorders in Canada: impact of disease prevalence and cost

Abstract

BackgroundAuthors from the Canadian Agency for Drugs and Technologies in Health (CADTH) presented an analysis of submissions to the Common Drug Review (CDR) between 2004 and February 3, 2016 for drugs for rare disorders (disorders with a prevalence of <50 per 100,000).ObjectiveThe aim of this analysis was to examine the same CDR submissions to evaluate whether the negative reimbursement recommendation rate, clinical evidence of efficacy and statements concerning the drug’s cost in the CDR reports varied with the prevalence of the disorder treated by the drug grouped into three decreasing categories: <50 to >10, ≤10 to >1, and ≤1 per 100,000.ResultsAs the prevalence of the treated disorder decreased, the median daily cost of the drug, the negative recommendation rate and the proportion of submissions with statements in the CDR reports highlighting the cost of the drug increased, while the proportion of submissions with acceptable evidence of clinical efficacy decreased. Moreover, although the CADTH authors reported that only two submissions received a negative recommendation due to a “lack of cost-effectiveness/high cost,” high cost was mentioned in the CDR reports of 15 drugs with negative recommendations, all for disorders with a prevalence of ≤10 per 100,000.ConclusionsThe aggregated analysis of CDR submissions for drugs for disorders with wide ranging prevalence rates concealed information of concern to patients. The negative reimbursement recommendation rate and the significance of cost in the CDR assessments increased as the prevalence of the treated disorder decreased. Since 2012, the manner in which high cost drugs for rare disorders have been dealt with by the CDR has changed. Cost has ceased to be a factor in negative recommendations but is included in criteria accompanying positive recommendations. This trend is associated with the integration of the CDR process with the system for price negotiation between public drug plans and pharmaceutical companies.

Do reimbursement recommendation processes used by government drug plans in Canada adhere to good governance principles?

“…A 2017 analysis of recommendations for rare disorder drugs indicates that an objective of the CADTH-pCPA integration is to ensure that a negative recommendation results in no pCPA negotiation, while a positive one sets up factors for inclusion in the negotiation (usually the need for a price reduction) between the pCPA and pharmaceutical manufacturer. 24 The analysis further demonstrated that a drug’s cost is associated with the likelihood of a negative CDR recommendation; for drugs used daily that had an estimated annual cost of less than CAN$55,000, the negative recommendation rate was 17%, compared with a rate of 74% for drugs costing more than CAN$55,000. 41…”

“…CADTH does not publicly acknowledge having a cost-effectiveness ratio threshold for assessing drugs, but evidence exists to suggest that CAN$50,000 per quality-adjusted life-year, first proposed in the early 1990s, 23 is used although not consistently applied 18 , 19 (a higher threshold appears to be used where there are unmet therapeutic needs or a lack of alternative options and for rare disorder and oncology drugs). Negative recommendations are frequently based on the expert committee’s opinion that a drug’s efficacy evidence is inadequate 19 , 24 despite having been assessed by Health Canada’s regulatory review as acceptable. While regulatory and HTA reviews have different objectives, 25 this can result in CADTH’s committees duplicating work already done by the federal agency.…”

Impact of rarity on Canadian oncology health technology assessment and funding

“…Although many international HTA agencies have not established a definition of rarity (including an incidence and/or prevalence threshold), there is consistent recognition that rare diseases are often severe, chronic, seriously debilitating, degenerative, life threatening, with no real alternative treatment (17)(18)(19). However, as there is no universally accepted definition, we used incidence as a mechanism to operationalize rarity since it can be measured and quantified.…”

What does the new ontario pharmacare plan offer children and young adults with rare disorders?

“…In a recent analysis of 55 CDR recommendations for 42 rare disorder drugs submitted between 2004 and February 2016, 11,12 18 reimbursement recommendations pertained to 16 drugs for rare disorders that commonly manifest during childhood (Table 1). Of the 18 reimbursement recommendations, 12 were negative.…”