Page 16 - HFA Dateline 2022 Special Edition

“Anything that can safely and The potential for gene therapy
access issues raises even more
effectively make a positive difference unanswered questions, according

is a good thing. Our job is to help to Wilkes. Will those who meet
eligibility criteria be able to get gene
people understand what the risks and therapy near them? “A good majority
of bleeding disorder patients get
benefits are. Some people are going to their treatment from a federally

be early adopters and some aren’t.” funded hemophilia treatment center,”
she said. “It’s pretty reasonable to
think that not all of those are going
—Sonji Wilkes
to offer gene therapy. You might not
be able to drive 30 minutes down the
road to get treatment. It might be
gene therapy in young children with immune reaction can require some the next state over.”
hemophilia,” he said. “This platform people to take potent corticosteroids
of therapy likely will not result in (such as prednisolone) to suppress Also unanswered is the question of
long-term expression in a young this immune response. payment for costly gene therapy
child because the liver is actively treatments. “We know already that
growing.” “Eventually, these AAV protein payers are slow adopters to any new
elements are cleared and there’s drug a lot of times,” Wilkes said. “We
Also potentially excluded are people no more immune response,” Pipe don’t know the cost and whether
who produce certain antibodies that said. “You’re able to come off payers are going to be willing to pay
may make gene therapies ineffective. the immune-suppressive therapy. for it. There’s a lot of questions about
“The human immune system is pretty Hopefully, on the other side of how the payment model is going to
smart, and it has a long memory,” that, you end up with a sustained be set up to pay for this. And I don’t
Pipe said. “We all get exposed to expression of your FVIII or FIX.” think any of us have figured that out
natural adeno-associated viruses yet. We’re at the mercy of how payers
in the community over the course Unanswered Questions end up deciding how to do this.”
of our lives, beginning in early With all its potential, unanswered
childhood.” questions remain around gene Pipe agreed that there are some
therapies for people with bleeding important unknowns around gene
These viruses don’t cause disease, therapy. “Are we going to get a
but our immune system sees them disorders. Will gene therapy good enough outcome for these
and produces antibodies against treatments produce consistent patients for them to embrace some
them. “Unfortunately, we’ve found levels of factor in every person? uncertainty with what levels they’re
that as many as 50% of the patients Will the therapy’s benefits eventually going to achieve, whether they’re
we screen for clinical gene therapy wear off? And if they do, can the going to get a good response and
are not eligible because of these same person be treated with gene how long it’s going to last?” he said,
cross-reacting antibodies,” Pipe therapy again? noting that some people might
said. “When someone is interested “Different patients end up with also be concerned about potential
in gene therapy, the first thing we different results,” Clark said. “A big unknown adverse events.
do is test them for these neutralizing thing with gene therapy is it seems it’s
antibodies.” not always reproducible. There’s a lot Still, for eligible patients, gene therapy
of things in hemophilia that we don’t offers the promise of producing
Another concern is that in some enough of their own factor to avoid
people, the infused gene therapy really understand, including exactly the need for prophylactic therapy.
may trigger a significant immune what determines how people bleed. “They can live their lives,” Pipe said.
reaction—their body sees the AAV That’s one of the problems with gene “It’s a one-time treatment that could
carrying the gene as a threat and therapy. We’re showing that it works, potentially last a decade or more.”
releases immune cells to fight it. An but there’s still a lot of unknowns.”

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16 DATELINE FEDERATION < www.hemophiliafed.org