The Pharmacologic Properties of LAIs and Patient Preferences

In this video, Sanjai Rao, MD, DFAPA, Associate Clinical Professor of Psychiatry, Associate Residency Training Director, University of California, San Diego, explains the  pharmacologic properties of long-acting injectables (LAIs) and how this treatment option impacts patient preferences.

Dr Rao recently spoke in a Psych Congress Elevate session titled “Clinical Profile and Considerations for Use of a Long-Acting Injectable Treatment in Adults With Schizophrenia” and he shares more insights on this topic here:

LAIs Offer Opportunity for Increased Medication Adherence in Patients With Schizophrenia

Effective Communication Strategies to Implement LAIs Into Treatment Plans

LAIs for Schizophrenia: Misconceptions and the Future of the Treatment

Read the transcript:

Hi, I'm Sanjai Rao. I'm a clinical professor of psychiatry at the University of California, San Diego, and an attending psychiatrist at the [Veterans Affairs (VA) Medical Center in San Diego].

My practice is centered around acute care and inpatient psychiatry, and I have the good fortune of being able to work with residents and medical students every day. That's most of what I do. I practice clinical inpatient psychiatry in the setting of training residents and medical students.

I also have the good fortune of being able to participate in events such as this.

The pharmacologic properties of LAIs

When I think of the pharmacologic properties of LAIs, there are a few different categories that I'm thinking of. The first is, of course, what drug is your LAI based on?
You have older-generation drugs, things like haloperidol and there's fluphenazine, and those have LAIs associated with them. For the newer medications, you've got one olanzapine LAI, and then most of the other ones that we're looking at are risperidone-based LAIs and aripiprazole-based LAIs.

That's the first key difference is, which drug is your LAI based on? My advice to people who want to start their patient on LAI is first, figure out which drug they're going to respond to, and then if you find a good drug that they respond to, then that's your LAI. That's the one that you should use. That's one.

The second big thing I think about is how you start the LAI. Each of the different LAIs has its own initiation regimen. With the older drugs, that typically used to be, you'd give them their first injection, you'd have to an oral overlap.
With haloperidol, later on, we figured out that you could load it like you load the newer LAIs by giving two injections a week apart at a higher dose than what your maintenance dose was going to be.

With the newer LAIs, there's also this separation between how you load them. Some of them require oral overlap for anywhere between two to three weeks when you first give the LAI.
Others have second-loading injections, where you'd give one loading injection and then another one, and that brings their drug levels up quickly.More recently, we've got a couple of LAIs where you can either do the loading injections in the same day so that you don't have to wait several days or a week in between. You don't have to do any oral overlap.

We even now have an LAI -- one of the risperidone-based LAIs -- where there is no second loading injection. You just give them a first injection. Also, a little bit of difference is administration site. Most LAIs are given intramuscularly, but we do have one new one that's given subcutaneously, so there's a little bit of a difference there.

The final thing I think about is, what's the duration that your maintenance injection is going to last? This is just a function of the effective half-life of the LAI. When you put an LAI into a muscle, depending on how hydrophobic it is -- basically, how fat-soluble it is -- it will take more or less time to come out of that muscle. The longer it takes to come out of that muscle, the more you can inject in there, and the longer the effect of half-life is. If you have an LAI with an effective half-life of about a month, you're going to dose it about once a month.

If you have an LAI with an effective half-life of two months -- for example, one of the aripiprazole LAIs has an effective half-life of two months -- you can extend the dosing out to two months.

There's a risperidone-based LAI or a paliperidone-based LAI that has an effective half-life of three months. You can dose that thing every three months. Those are the key qualities I look at.

What medication is it based on? You should choose one that's based on the medication that you already know works for the patient. How do you initiate it? This is relevant if you're worried about, is your patient going to follow through with an initiation regimen.

If you're worried about that, you probably don't want to choose an LAI that's got a long oral overlap or where they're going to leave and they're going to have to come back for something else in order for that initiation to be successful.

You think about dosing interval, which is, essentially, how long would you like to go between doses? If it's desirable to go more than a month between doses, then you're going to have to pick one of the particular LAIs that's got a half-life that can support that.

How do LAIs impact patient preferences?

This is a really interesting question. Patient preference in LAIs. The classical thinking on this is that patients don't like injections and, therefore, it's going to be hard to talk them into LAIs. The evidence we have suggests that that's not true at all.

That if you truly give patients a choice, meaning you present the LAI in a way that is fair and not in a way that just emphasizes the fact that you want to give the patient an injection, if you present them a valid choice and get true informed consent from them, many of them are going to be willing to take an LAI.

There's data out there that support that. That's where I condone. You have the new APA guidelines that say you can give LAIs to patients who prefer them. Preference requires education, and so that's the way I think about that.

Many, many patients who you offered LAI to in a way that is fairly representative of what the LAI can do for them and emphasizes both the strengths and the potential side effects of LAIs, that leads to more patient preference for LAIs than you might otherwise think.

Dr Sanjai Rao is an Associate Clinical Professor of Psychiatry and Associate Residency Training Director at the University of California, San Diego (UCSD), and the Site Director for Residency Training at the VA Medical Center in San Diego, CA.  A lifelong clinician educator, Dr Rao’s clinical practice is focused on inpatient and acute care at the VA, with an emphasis on teaching practical psychopharmacology to the many trainees he supervises. Dr Rao coordinates the UCSD Psychiatry Residency curriculum and has received a number of teaching awards based on his clinical and academic work, including the APA Irma Bland Award for Excellence in Residency Teaching.

Dr. Rao received his undergraduate degree from Stanford University, California, his medical degree from the University of California, San Diego, completed his residency at UCSD, and is board certified in general psychiatry and consult-liaison psychiatry. He is also the Immediate Past President of the San Diego Psychiatric Society and an APA Distinguished Fellow.