Biosimilar makers will increasingly use post-grant reviews
(PGRs) – a type of proceeding available at the Patent
Trial and Appeal Board (PTAB) – to cut down US patent
thickets on biologics instead of inter partes reviews (IPRs),
according to in-house counsel.
Sources at global pharmaceutical firms say explain that PGRs
are better for challenging biologic registrations at the PTAB
because biologic patents often have broad specifications that
make them vulnerable to description attacks.
While both forms of post-grant proceeding have been
recognised as cost-effective ways to invalidate patents
compared to traditional litigation, PGRs can be used to launch
written description attacks while IPRs can only be used to
challenge patent prior art.
PGRs have yet to become a popular tool for biosimilar makers
because they can only be used against patents with a priority
date later than March 15 2013. But sources point out that the
next wave of biologic patents coming to grant were filed after
2012 and have a later priority date.
"We have not filed any PGRs as of yet but will certainly be
using them for future products," says the global IP head at a
pharmaceutical company. "PGRs will definitely be more popular,
or at least as popular, as IPRs in the biosimilar space."
The head of IP for biosimilars at an innovator drug company
agrees, and adds that she has wanted to use this type of
proceeding for a long time but could not because of the
post-2012-filing start date.
She says that PGRs will be another useful tool for
pharmaceutical companies to ensure freedom to operate for their
biosimilar products, which particularly challenging in the US
where they are often blocked by enormous patent estates.
The planned worldwide launches of biosimilars for
AbbVie’s blockbuster arthritis-treating drug
Humira emphasises this difficulty. The drug was
launched as a biosimilar in the EU in October 2018. A US
version is not expected until 2023.
"Patent thickets are a problem in
Europe but not as much as they are in the US," says the
biosimilar head of IP for an innovator firm. "These estates
currently are not seen as anti-competitive and yet an
originator could have five inventions and turn it into 50
patents just by filing 10 divisional patent applications for
"It is now just a numbers game and not a matter of IP
PGRs and IPRs were both introduced by the America Invents
Act in 2012 – and so far the latter proceeding has
been the most used across all industries at the PTAB. According
to the USPTO, 8,476 proceedings out of 9,175 (92%) at the board
between September 2012 and 2018 were IPRs. Only 139 (2%) were
Covered business methods (CBMs), the only other form of post
grant proceeding at the PTAB, were also more popular than PGRs
– with 560 petitions.
Sources say that they have largely relied on IPRs to attempt
to cull biologic patent thickets at the PTAB, but that could
change as PGRs become increasingly applicable to biosimilar
strategies. After all, PGRs offer the same benefits as IPRs and
more – which means drug companies’
enthusiasm for IPRs is a good indicator of PGR popularity
The head of IP for biosimilars at a generics drug company
says that, given the popularity of the IPR system in the
biosimilar world, PGRs with their broader scope will quickly
become very popular with drug companies.
"IPRs are very commonly used for biosimilars," he says.
"Just in my own portfolio here, I am defending against nine
IPRs brought against my company’s patents, and my
team has filed around 15 in the last couple of years as a means
to clear the path for biosimilars."
The deputy general counsel at an innovator drug firm adds
that his company has also been attacked by multiple IPRs and he
suspects that it will have to fend off biosimilar makers taking
advantage of administrative challenges in the form of PGRs as
But there are two differences between IPRs and PGRs that
might curb biosimilar makers’ enthusiasm for the
report from RPX Corporation suggested that an IPR could
cost anything between $100,000 and $700,000. That figure would
be higher now because the USPTO increased IPR fees by 33% and
PGRs costs by 27% in 2018. Yet an IPR is still cheaper than a
The innovator firm’s biosimilar head of IP says
that PGRs might cost her firm anything up from $1 million per
patent, which is about 10 times more expensive than a standard
opposition. But she adds that given the potential usefulness of
the proceeding type, this cost may not significantly limit the
number filed over the next few years.
The second factor is time. Unlike an IPR, a PGR must be
filed against a patent within nine months of its grant, which
would force biosimilar applicants mapping IP protection for a
brand product to be more diligent in establishing an IP
portfolio early on.
"This timing cut-off is one reason why PGRs may not reach
the levels of popularity of IPRs," says the generic
firm’s biosimilar IP head. "It is questionable
whether a biosimilar applicant is going to want to invest $1
million to $2 million attacking a patent many years ahead of
its likely biosimilar launch date."
The global IP head at a pharmaceutical company does not
believe these factors will dramatically reduce future PGR
popularity because of the importance of challenging patent
thickets and reducing risk when it comes to freedom to
He and the innovator firm’s biosimilar head of
IP agree that global drug firms are likely to embrace the
proceeding’s provisions because they are already
used to the nine month cut off for European oppositions and
they will lead to earlier patent clearing in the US, which
benefits the biosimilar industry.
Better for innovators?
One may argue that the potential transition from IPRs to
PGRs among biosimilar makers in the US is a good thing for
biologic patent owners.
The deputy general counsel at an innovator drug firm says
that IPRs are particularly frustrating because they undermine
the litigation scheme set up by the Hatch-Waxman Act and can be
used to challenge a patent at any time.
He says that innovators want a front-end quality for their
patents, which is established by a quality examination and,
more importantly, an early challenge.
"I do not mind PGRs as much as IPRs because we are used to
the European opposition system and the idea that companies can
try to attack patents within nine months of grant.
"Nine months is also early in the drug development process,
which is good for us. It is after you have invested millions of
dollars and developed the market that a patent attack really
"On the other hand, I cannot tell management that they have
a predictable patent if at any given time they can face
challenge after challenge from IPRs."
He adds that his company and others like it are advocating
for the PTAB to use its considerable discretion when
considering whether to accept an IPR petition, and for it to
consider that there may be better ways to administer justice
than serial of parallel cases against a patent.
US biosimilar makers are ready to embrace PGRs to better
pave the way for their lucrative biosimilar products. The next
wave of biologic patents will be a good test for their
enthusiasm – but perhaps not even high costs or
efficient planning with stop them.