The abbreviated development pathway is described in the Biologics Price Competition Innovation
Act of 2009.
And in that act is stated the FDA has the ability to license a biosimilar product based
on comparisons between the biosimilar and the reference product, along with FDA’s
previous finding that the reference product is safe and effective.
And this is the totality of the information that allows for the development of these products
along the abbreviated licensure pathway.
The goal of a biosimilar development program is to demonstrate biosimilarity to the reference
product.
It’s not to establish safety and effectiveness of the proposed biosimilar.
So FDA recommends that sponsors use a stepwise approach to generate the data to support a
demonstration of biosimilarity.
This really ensures that only the necessary studies that need to be conducted are conducted,
which is in line and consistent with the principles of an abbreviated development pathway.
An abbreviated licensure pathway isn’t a lesser standard in any way.
The biosimilar products that are approved are based on the same standards of safety
and effectiveness that we have for all products that are licensed by the FDA.
The abbreviated licensure pathway really gets at identifying areas of development that don’t
need to be repeated scientifically, which allows for the development of these products
to be faster and to come to market quicker and improve options for patients.
Analytical data is the foundation of biosimilar development.
A variety of different analytical studies are conducted by the sponsor and are evaluated
by FDA to determine if the proposed biosimilar meets the standard of highly similar to the
reference product.
The data from the studies is used to characterize the quality attributes of the proposed biosimilar
and is used to help identify any potential differences between the biosimilar and the
reference product that could have impact on clinical performance.
There are a variety of studies that are used to support a demonstration that the proposed
biosimilar has no clinically meaningful differences compared to the reference product.
It can include pharmacokinetic and pharmacodynamic data between the biosimilar and a reference
product that’s really comparing exposure response profiles between the two products.
There’s a clinical immunogenicity assessment that looks for differences between the products
in terms of the incidence and severity of human immune responses.
And finally, there are additional clinical studies which are conducted, really, only
to address any remaining residual uncertainty that remains after the conduct of the studies
that I previously mentioned.
And it’s really all of these different pieces of information that feed into FDA’s finding
and determination that there are no clinically meaningful differences between the proposed
biosimilar and the reference product.
If a proposed biosimilar product is highly similar to the reference product and the totality
of the evidence supports biosimilarity, then it’s possible for a biosimilar manufacturer
to justify approval for some or all of the indications that the reference product is
licensed for without directly studying those indications themselves.
We don't extrapolate the conclusion of biosimilarity from the studied indication or population
to a different indication or population.
We're extrapolating a bigger concept than that.
It’s really taking all of the data that’s in the biosimilar application, along with
FDA’s previous finding and reliance that the reference product is safe and effective
for those indications, along with the information or knowledge and other scientific factors
that are relevant and important to the indication.
So taking, in total, this comparative data—FDA’s previous finding of safety and effectiveness,
that is—and the sponsors’ justification, that’s the basis for extrapolating from
the reference product to the biosimilar.
And extrapolation really is at the heart of a biosimilar development program, because
it gets to the abbreviation portion of this pathway.
And it really allows for products to be developed faster and brought to market quicker.