Australia has moved ahead of the pack in allowing pharmacists to substitute biosimilar medicines for their biological equivalents. However, the move has not been universally welcomed.
Pharmacists have been granted, from 1 July 2015, the controversial power to substitute a biosimilar medicine in place of a biological drug as part of the Federal Government's 2015 PBS reform package.
What is a biosimilar?
A biosimilar medicine is a version of an already registered biological medicine (the reference medicine) that has demonstrable similarity in physiochemical, biological and immunological characteristics, efficacy and safety. Biosimilars are similar to a biological medicine that has already been approved but for which the patent has expired.
Biosimilars differ from generic medicines, with the latter having simpler chemical structures, allowing them to be developed to be the same as the reference medicine. Because of both the complex nature of biologics and the way they are made, even though biosimilar drugs act in the same way as the original patented biologic, they may not be exactly the same.
The natural variability that occurs in the production of biological medicines means that biosimilars are similar, but not identical, versions of a biological medicine.
Not only are there minor differences between reference medicines and their biosimilars, there are minor differences between batches of the same medicines as a result of the complex, biologically-based methods of producing the medicines.
Show me the money
The key to the government's interest in these medicines is flagged in a TGA fact sheet which states that: "The availability of biosimilar medicines in Australia encourages competition, which could, in turn, lower the price that the government pays for biological medicines and biosimilars".
In fact, it has been estimated that pharmacy-level biosimilar substitution will save the Government at least $880million on the PBS, according to Department of Health figures presented to the Senate Estimates Committee in June.
The process of substituting a biosimilar medicine will work similarly to the existing generic substitution framework, and as with that scenario substitution is not allowed if the prescriber has ticked the 'brand substitution not permitted' box.
As with all other brands available and listed as suitable for substitution, such biosimilars will be given an 'a-flag'.
Where the PBAC recommends a biosimilar for listing on the PBS, it will also consider whether the biosimilar and its reference medicine should be substitutable.
The PBAC will only recommend that substitution be allowed where the clinical evidence supports this. In line with the usual practice for all PBS listings, the government makes the final decision on whether to list the biosimilar on the PBS. During this assessment process, PBAC will also consider whether the biosimilar should be listed to allow substitution by a doctor or pharmacist. This will be done on a case-by-case basis.
A mixed response
The move to allow pharmacy-level biosimilar substitution has been welcomed by many in the profession. In an online Pharmacy News poll, almost 60% of respondents said they agreed pharmacists should have the power to switch patients to approved biosimilar medications where appropriate.
But not everyone agrees with the decision, with criticism of the move from allied health and consumer groups as well as from the originator pharmaceutical industry.
Medicines Australia CEO, Tim James, said more research was needed, and the move was "out of step" with the rest of the world.
"On biosimilars and across our health care system, notions of safety first, of do no harm and of putting into practice, the precautionary principles should always come first," he told the Senate Estimates hearing.
Leanne Wells, CEO of the Consumers Health Forum, said there was "a consistency in the concern and opposition from clinical and consumer groups concerning the 'a' flagging of biosimilars and substituting them at the pharmacy level."
"There was also consistency in the view that decisions to substitute should only be made in the context of the therapeutic doctor- patient relationship. This is a really complex, evolving area of medicine and underlines the need for clinicians, dispensers and patients to have access to independent and authoritative information."
The decision attracted international attention with the Alliance for Safe Biologic Medicines - a US alliance of healthcare groups - saying Australia would be breaking "widely-held international standards by becoming the first and only nation to allow pharmacy-level substitution of biologic medicines without physician involvement".
"Allowing automatic substitution of biosimilars is an enormously retrograde step for Australia. One which is completely out-of-kilter with world best practice and which has the potential to reduce the standards of safe use of biosimilars for patients," said consumer advocate Stephen Murby, a member of the alliance.
At home, the AMA were not so critical of the decision, saying they were satisfied with the regulatory arrangements introduced for biosimilars, but that it was important that doctors are aware of the potential implications for their patients.
Former Pharmacy Guild of Australia national president Kos Sclavos said the CHF criticism demonstrates their lack of understanding about the issue, but he expects the organisation to "back flip".
"There is hypocrisy in their comments given past positions on PBS savings," he said. "The views of real consumers show they are happy to trust ... pharmacists regarding safe treatment choices."
The Pharmacy News poll occurred in the wake of the PBAC recommendation to list an infliximab biosimilar - Inflectra - for the same indications as its comparator drug, Remicade during their August meeting.
Health Minister Sussan Ley said the PBAC recommendation recognises the rapid growth in this type of treatment by Australians, with five of the top 10 drugs subsidised on the PBS now biologic drugs that would cost patients $400-$1700 per treatment without taxpayer subsidisation.
"This has in turn seen spending increase from about 4% of the total cost of the PBS a decade ago to about a quarter of the PBS today," Ms Ley said.
The efficacy of the evaluation process was shown recently when the TGA's Public Assessment Report recommended against 'a-flagging' the biosimilar insulin glargine Basaglar. Biosimilars currently available in Australia (but not 'a-flagged') include:
Aczicrit, Grandicrit and Novicrit with the active substance epoetin lambda - all have been approved by the TGA but only Novicrit is listed on the PBS; and
Nivestim, Tevagrastim and Zarzio with the active substance filgrastim - all have been approved by the TGA and all are listed on the PBS.