After a biotherapeutic product has been placed on the market, competitors will often try to develop ‘biosimilar’ products and be ready to market them once the patents on the original biotherapeutic product have expired.

They might also try to develop ‘biobetter’ therapeutic products, which might be structurally or functionally different from the original biotherapeutic product.

The patenting issues that apply to biosimilars are different from those that apply to biobetters.

Patenting of biosimilars

A biosimilar may be defined as “a biotherapeutic product which is similar in terms of quality, safety and efficacy to an already-licensed reference biotherapeutic product” (World Health Organisation). The reference biotherapeutic product will be one which has already passed the relevant clinical trials and a marketing authorisation will have been granted for it. After the patents on the original biotherapeutic product have expired, other drug companies will often try to produce such biosimilars in order to exploit the market for that biotherapeutic product.

From a patenting perspective, the biosimilar product is likely to be structurally identical (or at least very similar) to the reference biotherapeutic product. Hence any patent claims to the biosimilar product are likely to lack novelty over the (known) reference biotherapeutic product.

However, it might still be possible to patent the following:

  1. New formulations comprising the biotherapeutic product.
  2. New combinations comprising the biotherapeutic product and other active agents.
  3. New dosage regimes using the biotherapeutic product.
  4. New processes to make the biotherapeutic product

Patenting of biobetters

In order to be patentable, any patent claims to biobetters will have to satisfy the standard criteria for patentability: the claimed biobetter will have to be novel and inventive over everything in the public domain at the filing date of the patent application to the biobetter, including everything which is in the public domain at that time about the reference product and any biosimilars.

By definition, biobetters will be structurally different from the reference biotherapeutic product and hence they might well be novel for this reason alone. For example, compared to the reference biotherapeutic product, the biobetter might:

  1. Have a different amino acid sequence.
  2. Be a fragment of the reference product or a chimeric product.
  3. Have a different glycosylation pattern. iv. Have different attachments, such as PEGylation.

The inventive step of the biobetter is likely to be judged on whether or not the differences (such as the above) over the reference product are not obvious, and whether the biobetter has surprising or unexpected properties compared to the reference product. Examples of such properties could, for example, be that the biobetter has a significantly longer half-life, an unexpectedly higher enzyme activity or surprisingly better efficacy.