Selexipag: Where does it fit in the treatment jigsaw?
After a lengthy battle for access, Selexipag was approved as a treatment for pulmonary hypertension across the UK in April 2019. We caught up with Neil Hamilton, consultant pharmacist at the Sheffield Pulmonary Vascular Disease Unit, to sort the fact from the fiction.
First things first, what exactly is Selexipag and how does it work?
Selexipag is a new therapy which works on the prostanoid pathway. It dilates blood vessels, allowing more blood to flow through the lungs and around the body.
The difference with Selexipag is that it is a tablet as opposed to the more complex forms of prostanoid that are currently available working on that pathway; which must be nebulised, continuously infused through an intravenous line or given subcutaneously.
So, there are some convenient advantages with Selexipag and lots of patients might prefer to take a tablet as opposed to some of these other difficult options.
What has the clinical trial shown?
The clinical trial for Selexipag was the largest ever undertaken in pulmonary hypertension. It was a worldwide study and many centres across the UK were involved in recruiting patients. It showed that Selexipag could slow or prevent worsening for our patients.
In the study, patients could take Selexipag on its own or in combinations with other background treatments that they might have already been on – but whatever the combinations were, Selexipag showed a benefit over the placebo.
Who is Selexipag suitable for?
It’s not for everybody, and there will be some patients who won’t be suitable because of the type of PH they’ve got. We are somewhat restricted by what the NHS commissions in terms of who we can prescribe it to, but those restrictions are born out of the data and the evidence that came from this big clinical trial, so there are good reasons for it.
It is for stable patients, to prolong their journey with PH and prevent them from getting worse. It’s not a drug for treating someone who is declining.
Every case must be weighed up on its individual pros and cons. In the UK some patients must already be on certain therapies in order to be eligible to receive Selexipag.
So, it’s not for everybody but it is a really important addition to the armory of treatments available.
Is Selexipag a replacement for IV therapy?
We don’t see Selexipag as a straight replacement for either nebulised or IV therapy.
If patients are getting worse to an extent that we would consider them for an intravenous drug, or we’re talking about other things such as transplantation, then Selexipag is not the right treatment for them.
We don’t see Selexipag as a straight replacement for either nebulised or IV therapy
However, this isn’t a blanket rule and there will be exceptions – for example where it’s difficult to give IV drugs or one of the more complex therapies. In these cases, a tablet may be the only thing that can be added in. It is worth stressing that we see those as very much exceptions, rather than the rule.
What should I do if I think Selexipag may help me?
My advice is if you think you might want to give Selexipag a try and you think it might benefit you, have a discussion about it next time you’re in clinic.
They are the experts and know you better than anyone else and will also have access to all your tests and all the results, so you can make a decision between you.
Selexipag isn’t for everybody but it may stop some getting worse and needing more intense forms of treatment. It does give us a really important option to try and delay worsening.
If Selexipag is right for me, what happens next?
Once we have agreed the decision with the patient to start Selexipag, we will begin something called ‘titration’. By that we mean patients start out on a very, very low dose and build up steadily for a number of weeks, which might be eight to twelve.
The reason for building up slowly is because we know the treatment may cause side effects, such as headaches, or nausea, or general tummy ache.
By pushing up the dose slowly, these side effects can be managed and hopefully won’t cause patients to stop their treatment.
Patients start out on a very low dose and build up steadily for eight to twelve weeks
They will likely have contact with their PH centre on a weekly basis during this time, which I think is really important.
This is exactly the same process we go through with titration of intravenous therapy but obviously that is taking place in a hospital bed rather than at home.
So, nothing new, nothing different, but managing the side effects and slowly increasing the dose is absolutely crucial.
Not everybody requires, or can tolerate, the same dose of Selexipag. There isn’t a set target – what we are aiming for is the top dose which can be tolerated. This is the dose just one step down from where they are experiencing the side effects.
To sum up, Selexipag is an exciting treatment option that’s now available for us to prescribe. It’s not suitable for everyone, and it’s not for those who are worsening, but it’s an important addition to the other treatments that we have available. If you think you would benefit from selexipag, please discuss with the team at your PH centre next time you are in clinic.