Introduction:

An orphan designation is granted by EMA for all new drug intended to treat a life-threatening or chronically debilitating disease, provided a maximum prevalence in Europe of 5/10,000 and when no satisfactory alternative method can be authorised, or, if such a method exists, the medicine must be of significant benefit to patients.

Besides, other drugs might have a target population as limited as orphans, without being designated as such.

Objectives:

To detect among the drugs approved for limited populations any impact of the orphan status on the assessment outcome of medical benefit (SMR) or improvement in medical benefit (ASMR) carried out by the French authority for health (HAS).

Method:

Levels of SMR and ASMR granted between 6/7/2016 and 13/05/2020 were analysed for orphan drugs and for those with target population limited to 33 500 patients in France (comparable to prevalence of rare disease < 5/10 000 as per EMA, and assuming a French population of 67 million). Comparison of SMR /ASMR levels was performed between orphans and non-orphan limited population drugs.

Results:

Among 104 orphans and 265 non-orphan limited population indications (new assessment), SMR outcome was “important” for 73,1% of orphan drugs and 76.7% of non-orphans. ASMR was assessed for 89 orphans and 192 non-orphans, resulting in high levels (ASMR I to III) in 21.4% of orphans and 13% of non-orphan indications.

Conclusion:

While there is no trend for a better SMR outcome in orphan drugs over those destinated to limited populations, ASMR outcome appears more obvious with orphans. The extend of medical need is one of the parameters considered for ASMR appraisal. It is also a main eligibility criterion to qualify for orphan designation. This might explain the better ASMR levels observed with orphans.