Hemlibra

[Milos]

Why is Hemlibra not approved for on demand therapy? Does anyone know?

[Shellye Horowitz]

As far as I understand, the mechanism for Hemlibra is different and it does not work on demand, but must build up in your system. People who are on Hemlibra still need to take factor if they get a bleed – but many bleeds are prevented by taking it.

Hemlibra is not the actual factor, but similar enough that it is able to help bind FIX to FX to continue the clotting cascade (as I understand it, but someone else may be able to explain it better). When having an actual bleed, factor is more effective to stop the bleed – Hemlibra is great to prevent bleeds – it is for prophylaxis.

[Milos]

Have there been cases of hemlibra stopping any mild bleeding?

[Shellye Horowitz]

It is my understanding that there are clinical trials right now for Hemlibra in those with mild hemophilia – again, taken regularly to prevent a bleed.

[Milos]

I’m trying to figure out what’s the point. FVIII has a range of normal values of 50% -150%. FVIII is consumed during bleeding but until it falls below 30% it is effective. And Hemlibra is consumed. However, unlike FVIII, only the booster level is effective. I guess that’s the point. In other words, Hemlibra is consumed very quickly if bleeding already exists. And they must not give it in large quantities because of thrombosis.

[Shellye Horowitz]

Hemlibra works differently than factor so it is a bit hard to compare. It is not meant to treat bleeds in real time, but to prevent them. It apparently keeps a person at the equivalent of a FVIII level @ 30% (look it up, don’t quote me) so that it is good to prevent spontaneous and mild bleeds.

[Milos]

That’s right.

[Milos]

I think I understood. Thank you.

[Milos]

Why cannot Hemlibra be administered intravenously?

[Shellye Horowitz]

That is not the way it was developed – it was meant to be a subcutaneous injection. I think the point was to create something that did not require IV administration, as that is easier for most people!

[Milos]

I know about that, but there are drugs that can be given in several ways: intravenously and subcutaneously and muscularly and orally. If Hemlibra could be given intravenously then it could act immediately. In other words, Hemlibra could be used as a diamond, and not just preventively.

[Milos]

I guess hemlibra contains something toxic in itself, so if it was given intravenously, it would be dangerous. When given subcutaneously, it is not resorbed but remains in the intercellular space. I think so as an ordinary citizen.

[Author]

Posts