Over 1,000 patients per year have been prescribed cladribine for relapsing-remitting multiple sclerosis since the indication was first listed on the PBS, official reporting shows.

The figures come from the 24-month analysis by the PBAC’s drug utilisation sub-committee, which also said there was a “shift in the market away from older generation RRMS treatments”.

The analysis, released last month, said in total there were 1,130 and 1,407 patients treated with cladribine in 2019 and 2020 respectively, the first two years of listing.

This represented about 7,300 scripts across both years –or about 2% of the total number of RRMS prescriptions. Overall prescriptions for RRMS had remained relatively stable from 2014 onwards, at approximately 45,000 per quarter.

Nevertheless the report noted changes in the RRMS market over time, particularly a move to oral therapies becoming the most preferred form of treatment over injections.

This was likely due to the “potential convenience associated with less frequent dosing”, the report said.

It also noted “a high proportion of injection prescriptions were initiated by GPs, despite the restriction specifying treatment by neurologist.”

“DUSC considered that it may have been due to coding errors for Authority Required (Streamlined) prescriptions. Additionally, DUSC commented it could have been due to cases of neurologists advising GPs of the appropriate treatment plan to which GPs would initiate treatment for the patient or the patient’s lack of accessibility to neurologists,” it said.

Fingolimod still accounted for over one-in-four of all scripts, however not all patients switching to clabridine were previously treated with fingolimod, the report said.

Patients were aged 44 years old on average at the time of initiation of RRMS treatment, with women accounting for 73% – numbers which were similar for clabridine in particular.

It followed Australian research published two years ago showing the drug supported a rapid and durable disease modifying effect.

The study comprised 90 patients, most on a Patient Familiarisation Program when cladribine was available during 2010-2011, with follow-up data from the MSBase registry.

It found about 80% of patients with adequate post-cladribine follow-up (n=66) were free from EDSS progression, driven by the patients with RRMS.

And 65% of patients were free from relapses two years after treatment.

A nucleotide analogue of deoxyadenosine, clabridine is also indicated for:

• Treatment of patients with Hairy Cell Leukaemia.
• Treatment of patients with B-cell chronic lymphocytic leukaemia in whom treatment with alkylating agents has failed.