Experts review how influenza vaccines have advanced in recent years and discuss misconceptions that people may have about standard-dose and high-dose flu vaccines.
Rodney E. Rohde, PhD, MS, SM(ASCP)CM, SVCM, MBCM, FACSc: Hello and welcome to this Pharmacy Times Peer Exchange, [where we’ll discuss] the vital role of annual flu vaccines in protecting public health. My name is Dr Rodney E. Rohde. I am a university professor at Texas State University where I serve as chair and Regents’ Professor of the Clinical Laboratory Science program [in San Marcos, Texas]. I’m a global fellow, and also the associate director for the Translational Health Research Initiative at Texas State. I will be your moderator today. Joining me today in this virtual discussion is Dr Randy McDonough. He is a co-owner of Towncrest Pharmacies, Towncrest Compounding Pharmacy, and Innovative Pharmacy Solutions, and a professor at Loma Linda University School of Pharmacy [in Iowa City, Iowa]. Also joining me is Dr Chad Worz, executive director and chief executive officer at ASCP [American Society for Clinical Pathology in Alexandria, Virginia], and finally Dr Adam Welch, who is an independent vaccine consultant and pharmacist at ETSU [East Tennessee State University] Health [in Johnson City, Tennessee]. Today, we are going to talk about several topics pertaining to the importance of annual influenza immunizations, including the different available vaccine formulations, and the ACIP [the Advisory Committee on Immunization Practices] recommendations in addressing barriers related to immunizing populations annually. Let us get started.
In this first segment today, we are going to be talking about some of the differentiations in available flu vaccinations. Dr Welch, how have influenza vaccines advanced in recent years, and how do you see these different vaccines impacting rates of immunizations? For example, adjuvant, quadrivalent, and recombinant vaccines. Please discuss the differences between these different vaccines.
Adam C. Welch, PharmD, MBA, FAPhA: The short answer is these vaccines have evolved a ton over the last 1 to 2 decades. 15 years ago we were making influenza vaccines using primarily chicken eggs. We developed this candidate virus early in the year, and they would spend the better part of the spring and summer replicating that virus in chicken eggs and creating the flu vaccine that we would use for that particular flu season. Technology has come a long way since then, and now we have, as you mentioned, recombinant vaccines, we have high-dose vaccines, we have adjuvanted, and we have cell-cultured vaccines. So we are not just relying on the chicken egg to replicate that virus anymore. What that means for patients is that we have more options. With these options, some of these vaccines have shown better efficacy outcomes, which means they can help prevent people from getting hospitalized or coming down with severe complications associated with influenza. So it’s exciting, the influenza market, but it is a lot of information for us as providers to have to keep up to date with.
Rodney E. Rohde, PhD, MS, SM(ASCP)CM, SVCM, MBCM, FACSc: Absolutely, that information overload sometimes can be very difficult for our patient populations. In that vein, can you talk a little bit about how that adjuvant can enhance or detract from immunogenicity and efficacy between those different ones, briefly?
Adam C. Welch, PharmD, MBA, FAPhA: An adjuvant is a compound that helps enhance the immune response of a particular vaccine. The adjuvant that’s in influenza is called MF59; it’s an oil-in-water emulsion. And what it allows you to do is it allows you to create a robust immune response from the same level of antigen that you would find in a standard-dose influenza vaccine. So we’re getting a higher effect with the same amount of antigen because of this adjuvant. So that efficacy can be helpful in certain populations.
Rodney E. Rohde, PhD, MS, SM(ASCP)CM, SVCM, MBCM, FACSc: That’s actually very important, especially when you get into those older populations that may not have the robust immune system that you’d normally see in someone else. Again, in that respect, how does the high-dose quadrivalent compare to the standard dose and even the recombinant vaccines in terms of efficacy?
Adam C. Welch, PharmD, MBA, FAPhA: So the similar idea is that we’re trying to boost the immune response in certain populations. And for this discussion, it’s people 65 and older who may have what’s called immunosenescence, that general weakening of your immune system as we age by providing a higher concentration of the antigen. So for the high dose, you have 60 µg of antigen vs 15 in a standard dose. That higher concentration is enough to elicit a stronger immune response in the 65 and older population. That stronger immune response means they can fight off influenza infection better and prevent hospitalizations and complications associated with it.
Rodney E. Rohde, PhD, MS, SM(ASCP)CM, SVCM, MBCM, FACSc: Dr McDonough, what are some of the misconceptions that people may have about standard-dose flu vaccines and high-dose flu vaccines? And how can health care providers in general address these? In other words, are all high-dose flu vaccines using adjuvants?
Randy McDonough, PharmD, MS, BCGP, BCPS, FAPhA: I’m not so sure that when patients come to me [they] have a misconception about high dose vs standard dose. I think it’s more a question [of], “what is a flu shot and why do I need one?” But I think as the new technology, as Adam talked about, has come out, it also made people question safety; [they may ask themselves,] “Is this really going to be OK for me?” I know when the high dose first came out, we started promoting that to our older patients. They asked, “Is this going to make me sick? Is this going to hurt more? “We explained to them that as you get older, your immune response may not be as great to a standard dose. And that’s the reason why you go to a high dose. So it’s really still talking to patients about the importance of having a flu shot, which flu shot might be right for them, especially for the older patient, and that they’re just as safe and very effective for them. We really try to educate the patients as much as we can.
Rodney E. Rohde, PhD, MS, SM(ASCP)CM, SVCM, MBCM, FACSc: That’s been my experience as well. When you’re dealing with anyone in the public, you tend to run across this. There’s so much information, even breaking down the vaccine types can be overwhelming. So that discussion is very important.
Randy McDonough, PharmD, MS, BCGP, BCPS, FAPhA: We spend a lot of time on a lot of education, especially trying to make sure that patients are aware of when they need to get the shot; make sure when they do get it, they get it as soon as they can when it becomes available [and] not to wait too long; and to be ready when that flu season hits.
Rodney E. Rohde, PhD, MS, SM(ASCP)CM, SVCM, MBCM, FACSc: Yes, exactly.
Transcript edited for clarity.