Zenrelia (ilunocitinib) is a new medication for treating allergies in dogs. In this episode, veterinary dermatologists Dr. Brittany Lancellotti and Dr. Tom Lewis discuss detailed analyses of clinical trials, patient stories, and comparisons with existing treatments like Apoquel. The conversation covers the drug’s mechanism, safety considerations, and the impact on vaccine efficacy. Real-world applications are reviewed, emphasizing the importance of multiple treatment options for allergies and working to find the underlying triggers. The episode also highlights advancements in managing skin and ear infections to prevent antibiotic resistance.
Table of Contents
An Independent Analysis of Safety and Efficacy of Zenrelia
[00:01:05] Welcome, everyone, to today’s episode of Your Vet Wants You to Know. Today’s episode is exciting because we’re going to be talking about a new medication to help dogs with allergies that’s called Zenrelia, or ilunocitinib.
I’ve reviewed other prescription medications in episodes 4 through 7, so if you want to hear about all of the different prescription options that you have for allergies, you can go back and listen to those and get some more information on the different options that are available. But I hope this episode provides pet owners some good information on this new option for their allergic dog, and also serves as a tool for veterinarians who may not have the time to be able to answer all of the questions that owners may have about a new therapy.
This is a prescription medication. Even though we will try to give you as much information as possible during this episode, this show is meant to be a resource only. We want you to reach out to your family veterinarian, who knows your individual pet and their medical history, so that you can ask any follow up questions that you might have, as each pet is different.
For transparency, I think it’s important for listeners to know that this episode is not sponsored by Elanco, the makers of this new drug, Zenrelia. In fact, very few of our episodes are sponsored, which helps us to maintain independence and integrity in the information that’s being presented.
If you would like to support our show, you can visit https://www.buymeacoffee.com/yourvet to buy Russell Sprout, our mascot, a puppuccino and help us continue to provide these independent episodes free from sponsorship.
Both today’s guest and I are regular speakers at continuing education events and conferences for veterinarians. Our talks have been sponsored by various companies, including Elanco, but everything we are going to be discussing today will be based on a combination of the available research and our clinical experience.
Welcome Dr. Tom Lewis
Dr. Lancellotti: Since this is a new drug that I haven’t used in my patients yet, I wanted to bring on a brilliant colleague, Dr. Tom Lewis, who has been involved in the clinical trials for Zenrelia. He and I have been reviewing the data coming from the safety and efficacy studies of this medication, and I know he’s going to offer valuable insight for pet owners and veterinarians who are looking for more information for their pet. Thank you so much for joining us and welcome, Dr. Lewis.
[00:03:13] Dr. Lewis: That was a very complimentary, flattering introduction. Thank you.
[00:03:19] Dr. Lancellotti: So, tell our listeners a little bit about yourself and your journey through Vet Med. What brought you to where you are today?
[00:03:25] Dr. Lewis: I always knew I wanted to be a veterinarian, starting in sixth grade. am a fourth generation Arizona native. I went to veterinary school at Colorado State. I married my college sweetheart, because she didn’t want anything to do with me in high school. But I always have loved this profession. I love veterinary medicine and I love veterinary dermatology. I especially enjoy, and have always been challenged by, the allergy. I like to think of myself as just a passionate allergist who tries to really get to the bottom of what ails these itchy dogs and cats.
[00:04:02] Dr. Lancellotti: Yeah. You have been involved in dermatology for quite some time. You’re one of the pioneers of this profession. Tell us a little bit about your practice.
[00:04:11] Dr. Lewis: So, I graduated veterinary school in 1986. I started my own company in 1981 and we just grew organically because there were so many regions where there was no veterinary dermatologist – even in the whole states of New Mexico, Utah, and so forth. I was just trying to fill needs, our practice grew, and I am proud to say I’ve now helped train 23 residents. I just have wonderful friends and colleagues in this profession.
[00:04:42] Dr. Lancellotti: That’s amazing. For those of you listening, a residency is a lot of work. We go through undergraduate school, then four years of veterinary medical school, and you can go on to general practice at that point. But to become a dermatologist, you typically have to do at least one year of a rotating internship. Sometimes, you do another year of a specialty internship, and then you do two or three years of a residency. During that residency, there’s a lot of things that you have to learn, and projects that you have to complete. So for you to have trained 23 residents is amazing. It’s really helped to build this college and this profession.
[00:05:20] Dr. Lewis: Thank you.
[00:05:22] Dr. Lancellotti: And you’ve participated in a lot of clinical trials as well, correct?
[00:05:25] Dr. Lewis: Yes. I love that aspect of this profession, and I have now participated in 29 trials, including the drugs we’re talking about today- two clinical trials involving Zenrelia. I was involved with three different aspects of Apoquel trials, and several with Cytopoint, one of the injectable products. They’ve not always been as exciting, rewarding, and helpful as the drugs that I just mentioned, but there have been many trials.
[00:05:51] Dr. Lancellotti: Yeah, so that’s a really helpful thing. Making these medications available to the pets that need them – doing these clinical trials and seeing what works, what doesn’t work, the safety, the efficacy, etc…
Clinical Trials for Zenrelia
Dr. Lancellotti: Can you tell us a story about a pet that comes to mind, when you think of some of the pets that you’ve treated with Zenrelia, during that clinical trial?
[00:06:09] Dr. Lewis: It’s just amazing to me, when I look back at the patients that were in the Zenrelia trial and review their data, I just love these examples. I have a patient named Chance who was a 10 year-old pit bull terrier when we enrolled him. And for a dog to enroll in a clinical trial like this, they have to have a certain level of itchiness. There’s a scale that we use to monitor the itch, and it’s a 1 through 10 or 0 through 10 scoring system. To be eligible, dogs have to be at least moderately itchy, which is 6 out of 10 on that scale. Chance was about a 7 when he enrolled in the study, and many of the patients that we see are especially bad in the month of March. Chance’s numbers actually started at 7, but five days later, he was down to 1.7.
[00:07:02] Dr. Lancellotti: How wonderful for this dog, that he was able to get the relief that he was.
[00:07:06] Dr. Lewis: Then, he went down to 1 on day 14. He did have a slight flare in March. He went back up to 3.6, which is still not nearly as bad as 7, but not as comfortable as we wanted him to be. But then that settled down as the pollen count went down, and his final score at the close out in June was 1.2. And then to bring an example home here – we tried to put him on Apoquel, but it just didn’t work. And Cytopoint did not work either. He did not tolerate a drug called Cyclosporine. He had too much gastrointestinal upset. The only drug that he could tolerate was steroids (methylprednisolone), and now he has a heart murmur.
[00:07:45] Dr. Lancellotti: Yeah, this really highlights the fact that not. Every allergy dog will respond to or tolerate a single allergy medication for their problems.
River, a Zenrelia Success
[00:07:55] Dr. Lewis: Let me tell you about another dog named River who came into our study with a itch score of 7.2. A week later it was 4. And by day 14, he was 1.4. Then, 1.8. the middle of March, at the end of the first month. As you know, we think of an itch level of 2 or less to be a normal dog. We have started to use the word remission when dogs’ itch level gets to a 2 or below. So by that definition, he was in remission and he stayed there. On day 56, at the end of the second month, he was 1.1. That’s pretty much where he stayed for the next several months. After that, he has been on steroids, Cyclosporine, Apoquel, and sometimes, in combination. Sometimes, he’s needed those drugs all at the same time. He continues to get reoccurring infections, despite a pretty intensive bathing regimen. So he still has these infections, which tells us that we have not controlled the inflammation of the skin. Not for lack of trying, but he still has these infections. And in a day and age of resistant staff, that has to be concerning – every time he goes back on antibiotics. He was completely controlled with Zenrelia, and today, he’s not controlled with three drugs.
[00:09:26] Dr. Lancellotti: Yeah, this seems like a dog. Whose allergies really just weren’t responsive to other medications that. We’re available. So it’s really awesome for us as dermatologists to have this new tool that maybe some of our previously unresponsive patients might have an opportunity to get relief with.
Trooper, another Zenrelia success
[00:09:42] Dr. Lewis: Then, there was Trooper, who is just this incredibly cute little terrier. He was one year old when he enrolled in the study, and was a 10/10. He was just miserable, and making his pet mom miserable too. So we enrolled him and he started to get better. On day five, had an itch level of 7, but he was down to 1.9 at the end of the second week. So he was already in remission.
He stayed below 2 for the remainder of the study. He did not have a flare in the spring. His final closeout itch level was 1.2. Since then, he has been on Apoquel, sublingual allergy drops (as we try to desensitize him), and periodically, he needs steroids because his itch level has bounced between 3 and 5. And with Zenrelia alone, he was in remission.
[00:10:35] Dr. Lancellotti: This must’ve been really satisfying to see in your patients and to be part of that clinical trial.
Response to Zenrelia May Vary
[00:10:43] Dr. Lewis: But on the other side, I also had a patient, Maxine, who started at 6.2, but the decrease was slow. We were only down to 5 at day 28. By day 56, we were still not in remission – we were at 2.9. Finally, at the end of the fourth month (which is when we closed out), our itch level was at a 1. So it took time. And realistically, not every dog is gonna do quite like Trooper, where they go from 10 to 2 in two weeks. We like to think and talk about those patients, but to be fair, we should be prepared to start a patient and go for two months.
[00:11:25] Dr. Lancellotti: I think you brought up some really interesting points with these few cases. With Chance, you mentioned that the other medications either didn’t control the disease or brought about side effects. Every allergy dog that we treat is its own individual snowflake. They’re not all going to respond to one particular medication, which is for me, what’s so exciting about having another tool in our allergy toolbox. We’ll be able to have another option for an animal whose allergies maybe don’t respond to certain things, or we’ve got some side effects that we need to worry about, either with Cyclosporine and that gastrointestinal upset that you mentioned, steroids and having the heart murmur, diabetes, or liver disease, etc. It’s really important to talk to your family veterinarian about the right option for your pet because not all allergy dogs are going to respond to the same thing.
[00:12:19] Dr. Lewis: Boy, that’s so true.
What is Zenrelia?
[00:12:20] Dr. Lancellotti: So let’s talk a little bit about this particular medication. What exactly is Zenrelia? And in very simple terms, what is this medication actually doing in the body?
[00:12:30] Dr. Lewis: Zenrelia is in the same class of drugs as Apoquel. This is called a Janus kinase (JAK) inhibitor, and there are 10 Janus kinase inhibitors approved for human use by the US FDA. Veterinary medicine now has two. These drugs block chemicals in the body called cytokines, and it’s basically how things get done. Some of the cytokines are involved with inflammation, the immune system, growth, and regulating all aspects of our bodies and our patients bodies. So in essence, Zenrelia tries to block the cytokines that are causing inflammation and itch, while leaving the cytokines that do good things alone. Zenrelia targets those cytokines that are involved with inflammation.
[00:13:24] Dr. Lancellotti: Yeah, that’s a great explanation for that.
Zenrelia Clinical Trials in the United States
[00:13:27] Dr. Lancellotti: I want to talk about some of the data that’s come out of these clinical trials. Can you describe what the study design was, in these projects, and what the statistics showed? What did you find interesting during that trial?
[00:13:43] Dr. Lewis: Absolutely. So there were two studies done in the United States. One was for dogs who had a confirmed diagnosis of atopic dermatitis, which is in essence, an allergic reaction to the various pollens, mold spores, and dust mites. That’s the number one allergy that both specialty practice and general veterinarians see.
In the other study, the dogs did not have to have a diagnosis of atopic dermatitis. They could be itchy for any other reason. They could have a food allergy or a flea allergy. It didn’t matter. Both studies went on for four months, and they both required the minimum itch level, and for the atopic dermatitis study, we had to have a minimum level of badness for the dog to qualify to enroll.
Both categories of itchy dogs showed significant improvement. I did not appreciate a difference in the response in the two groups. So in other words, it looks to me like the food allergic dogs maybe did just as well as the dogs with atopic dermatitis.
[00:14:47] Dr. Lancellotti: I often find that my food allergic patients take much higher doses and much stronger medications, in order to control their itch compared to animals with just environmental allergies.
[00:14:58] Dr. Lewis: Yeah, so we didn’t see a difference.
Comparing Zenrelia to Apoquel in a Head to Head Study
Dr. Lewis: The third study was done in Europe, and the European Union had a different study design. They required a head-to-head comparison between Zenrelia and Apoquel. In our two United States studies, dogs either got the study drug, Zenrelia, or they got a placebo or control drug. The European Union study (and there were four countries involved with the studies there, and multiple sites for both) really generated some interesting data. And this is where statisticians sometimes confuse me.
Basically, the study showed that Zenrelia was not inferior to Apoquel. I know. It’s hard to think about it that way, but all of the dogs in the European study showed improvement, of course, because there was no placebo group. Some graphs show the end point, and there’s no question that the average dog on Zenrelia ended up with a lower level of itch, compared to the dogs with Apoquel. To compare results, in the European study, they found that 77 % of the dogs on Zenrelia reached that remission itch score of 2 or lower.
[00:16:23] Dr. Lancellotti: Well, I think you’ve got some interesting information. It was a very big study. This wasn’t just with a small number of dogs. They used over 300 dogs (about 338) that had environmental allergies, and it looks like there’s a statistically significant improvement in the itch level in both groups, which is not surprising.
But what I think is very interesting (and something that I’ve seen in practice, as well) is that after the twice day dosing with Apoquel, when we initially start an animal on that medication, we have a certain number of animals that when dropped down to once a day dosing, unfortunately their itch does not continue to improve or maybe rebounds a little bit. Sometimes, there’s no difference and they do fine with just continuing on the once per day dosing, but the data points generated from this study show that there continues to be improvement using the once daily Zenrelia, compared to going down to once a day on the Apoquel. So it’s interesting to have another option, in order to have that level of comfort that the owner and their pet are looking for.
[00:17:29] Dr. Lewis: That’s an excellent point. When we look at the graphs of their itch level, twice daily Apoquel and once daily Zenrelia both gave, in essence, the very same great results. As you said, when Apoquel dosing went to once daily, we saw this slight rebound or increase in itch, and the Zenrelia dogs continued to get better, and some of the Apoquel treated dogs started to get a little bit more itchy. And by the end of the fourth month was where there was a significant statistical difference in the levels of itch. So that’s a very good point.
[00:18:03] Dr. Lancellotti: Yeah, and for those of you who may not be quite as familiar with running studies on new medications, when we have a medication that has already been established, and has been used in practice for quite some time, there are studies called non inferiority studies. What they’re looking is whether this new medication is going to be equivalent or non inferior. And so this study did show that there was non inferiority between Zenrelia and Apoquel. So that’s exciting to have that new option available to us, for those other animals that might need another option.
Using Zenrelia in Your Pet
[00:18:42] Dr. Lancellotti: Let’s talk a little bit about how this medication is used. Why might a veterinarian prescribe Zenrelia? And when an owner is giving this medication to their allergic pet, what should they expect to see?
[00:18:55] Dr. Lewis: If you have a pet who’s uncomfortable with the allergy (whether it’s a flare because of flea bites or the pollen count), Zenrelia could be an appropriate medication to use. What we see from the data and what I experienced in the trials – the improvement is quick. Not that they become normal overnight, but it’s a very fast acting drug. It’s absorbed quickly. It’s also metabolized out of the system quickly, should we ever need to stop it for any reason.
But what we expect to see, over that first week, is a noticeable, obvious reduction in itch, which can cause improvement over several weeks to several months. The side effects that we might see is going to be GI upset (vomiting or potentially diarrhea). We saw that both in our studies in the United States and in the European studies, as well. The rate of GI upset in the European studies, comparing it to Apoquel, was about the same in both drugs – about 10 to 13 %. I had no patients needed to stop the drug because of that. But those were the most common side effects that we saw.
[00:20:05] Dr. Lancellotti: Yeah, one of the things that I like about Apoquel, and why I’m excited about Zenrelia, is that it seems to be very well tolerated by most of the patients that I use it with. I still do things like physical exams and blood work on a regular basis, to make sure that I’m catching any abnormalities before they become concerning. Compared to some of our other medications like steroids, for example, the Janus kinase inhibitors seem to be something that the pets do much better with, in terms of minimizing those risks and side effects. Whereas with steroids, we know that they’re going to experience side effects, both short term and long term. So it’s really helpful for those animals that are sensitive to medications.
Boxed Warning for Zenrelia
Dr. Lancellotti: One thing, in particular, that we need to talk about is this boxed warning. There are some risks when using any medication, so we want to talk about the risks with this particular drug. You and I have looked through the data at length, from the initial vaccine study which led to the warning. Let’s describe the boxed warning, the study, and the outcome.
[00:21:12] Dr. Lewis: Absolutely. This warning is scary when you read it. There’s no question about it. Should I read it?
[00:21:19] Dr. Lancellotti: Yeah, let’s read it.
[00:21:21] Dr. Lewis: It’s the elephant in the room.
Based on results of the vaccine response study, dogs receiving Zenrelia are at risk of fatal vaccine induced disease and inadequate immune responses to vaccines. Discontinue Zenrelia for at least 28 days to three months prior to vaccination and withhold Zenrelia for at least 28 days after vaccination.
[00:21:44] Dr. Lancellotti: Yeah, that’s a big scary warning on there, huh?
[00:21:48] Dr. Lewis: It is.
Design of Vaccine Response Study for Zenrelia
[00:21:49] Dr. Lancellotti: In the original vaccine safety study, they wanted to determine the effects of this medication on primary vaccination. This helps family veterinarians to determine the benefit and the risk.
If you want more information about vaccines episodes. 49 through 51 are on puppy and kitten vaccines. And that’s. With my amazing fellow veterinarian. And sister-in-law Dr. Alina Barland. And as well as the rabies vaccine, specifically with Dr. Jess Torok.
[00:22:16] The population of animals for this study is not the same population of animals that we’re giving the medication to. They used 16 ten-month-old, unvaccinated beagles – these were puppies less than 12 months of age (which the medication is not indicated for animals less than 12 months of age) and they had never been vaccinated before. Again, this medication is supposed to be used for animals who have received their core vaccinations already, and just need boosters as they get older.
These beagles came from biosecure facilities (housed in an area where they should not be exposed to infectious diseases, to help make the study design more controlled). They wanted to make sure that these dogs had never previously been exposed to the viruses that they were going to be vaccinated against, or any other infectious diseases. When these animals were nine months of age, they were transported from one biosecure facility to another.
During the study design, they measured titers (antibody levels) to the different viruses, three weeks and one week prior to giving either three times the labeled dose of the drug, or a placebo, for a total of 88 days or three months. The 1st set of vaccines was given 28 days after starting the drug or placebo, and then they were given a booster vaccine a month after that. During the study, they measured vaccine titers at day 28 (the same day that they got their 1st vaccine), day 60 (a month after they got their booster), and then day 88. After discontinuing the medication, at that three month point, they then measured the vaccine titers again at four months, and then six months into the study (one month and three months after stopping the medication). And during that study, they also looked at weight, blood work, urine, and other immune markers (T helper cells).
Results of Zenrelia Vaccine Response Study
Dr. Lancellotti: What they saw was that one month after vaccination, all of the animals in the study, both the animals that had received the drug and the placebo dogs, had an adequate response to canine adenovirus 2, canine distemper virus, and canine parvovirus.
Two months after their vaccination, all of the dogs had an adequate response to the canine adenovirus 2 and the canine parvovirus, one of the dogs in the treatment group had a low titer for the canine distemper virus, and unfortunately, four of the treated dogs had low titers for rabies.
Three months after their vaccination (one month after stopping the medication), all of the animals who were still in the study had an adequate response to the canine adenovirus, the parvovirus, and the distemper, one of the treated animals and one of the placebo animals had low rabies titers. So three of those animals, who had a low rabies titer previously, had come back up and their titer levels were considered adequate, at that time.
Complicating Factors During Zenrelia Vaccine Response Study
Dr. Lancellotti: So this is where things get a little bit complicated, because we look at this and we’re like, “Why did these animals have low titers for these vaccines?
[00:25:27] Is it because their immune systems were over suppressed by this anti-inflammatory medication. And certainly that’s a possibility we need to consider when we’re evaluating risk and benefit of a new treatment option.
[00:25:38] Dr. Lancellotti: Unfortunately, during this study, dogs in the entire study became sick with a coccidiosis, which is a gastrointestinal parasite that can cause severe diarrhea in young animals. Some of them started showing signs before their first set of vaccines. It’s unfortunate, not just for the dogs who became sick, but because this GI parasite contaminant showed up, in what was supposed to have been a biosecure facility. This was a situation where these animals were not supposed to be exposed to infectious diseases, but somehow, it got into the facility. And that just shows you how pervasive some of these infections can be.
[00:26:20] These animals were also all living together as a group where that research was being conducted and with a contagious disease like this stomach bug, all of the dogs were at risk of getting sick.
[00:26:29] There were illnesses, in both the control and the treated dogs, with a range of severity. Some of them just had very minor illness, but two of the dogs in the treatment group were humanely euthanized as a complication of severe infectious disease and immunosuppression. This is a very unfortunate outcome and very sad for those dogs. The dogs in the treatment group with only minor illnesses did respond well to the vaccine.
The important thing for us to remember is that this is a lab study and not what happens in real life. So if an owner brought their pet into their family veterinarian for vaccines, and the pet was currently having severe gastrointestinal disease, they’re not going to be vaccinated. Right? The family vet is going to treat that GI disease, get that pet feeling better so that their immune system’s working, and then vaccinate them. If the immune system’s already trying to struggle with another disease process, it’s not going to respond well to vaccines. But because this was a lab study, they proceeded with the study design and vaccinated the dogs, even though the dogs were likely too sick to receive their vaccines in a real world setting.
When we talk about those markers that they were looking at, in terms of what the animal’s immune system was doing (those T helper cells, which are really important in response to vaccination), even the dogs in the control group had low T helper cells before being vaccinated, likely because of that parasite.
They found that one of the euthanized dogs had canine adenovirus type 1 in its liver. It developed a hepatitis (inflammation of the liver) that was severe enough that it did need to be euthanized. But this is a different virus than what we vaccinate for. While it does state on the label “vaccine induced fatal disease,” what they’ve actually demonstrated is that the virus, which was isolated from this dog’s liver, was different than the vaccine virus.
[00:28:25] So the additional information that has been gathered since this original information went to the FDA, shows that the modified virus in the vaccine that this dog was given was not the same as the virus that made this one particular dog sick. The virus that made the dog so sick was a different, very contagious hepatitis virus that may have gone undetected in some of the other animals in the study as well, but just didn’t cause as many problems in the other dogs. So this is a second situation in which a highly infectious disease was found in what was supposed to have been a bio-secure facility.
Zenrelia Vaccine Response Study - Lessons Learned
Dr. Lancellotti: I have spoken with the folks at Elanco about what they’ve learned from their experience during and as a result of this vaccine response study and how they plan to improve. The way in which their trials are conducted in the future. They’ve outlined a number of changes in how and where their studies will be performed to ensure safety and good use of the animals involved. They also have committed to more monitoring throughout their clinical trials and safety studies, which will really help to identify problems with the animals, get them the right treatments, and make sure the studies are okay to proceed with the study in light of having as much information as possible.
[00:29:39] Dr. Lewis: It really was a conundrum, for these dogs that were supposed to be free of pathogens, to be free of diseases. They had two different diseases. As I understand it, the hepatitis is also very contagious. And these dogs were living together and playing together. It’s almost certain that they all had hepatitis. And of course, if you have a young puppy with hepatitis, and give them three times a dose of Zenrelia, you’re going to get sick and not respond to vaccine. To the FDA’s credit, they can’t ignore that. Everybody was doing their job. It’s unfortunate that it happened this way. Elanco, who makes Zenrelia, was not doing the study themselves, they hired it out and it was just an unfortunate chain of events. But I think it’s important then to at least ask, “Okay, that’s why the label’s there, but what put the label there?” When you really dig deeper, I think that you can make your own conclusions, based on the science and what facts we know.
[00:30:43] Dr. Lancellotti: Yeah. As a scientist, when I’m interpreting the results of this study, the big takeaway for me is to not give Zenrelia to unvaccinated puppies, at three times the label dosing, especially when they’ve got a bad stomach bug. I wouldn’t reach for this medicine, in unvaccinated puppies, anyway. It is for dogs 12 months and older, and I think it’s also really important for us to stay within the label dosing, so that we can minimize risk when we’re using these medications.
New Vaccine Response Data from Zenrelia
[00:31:11] Dr. Lancellotti: So let’s talk about what the new vaccine study (that was presented at the International Society for Companion Animal Infectious Disease) showed.
[00:31:20] Dr. Lewis: The study that was just presented basically looked at 68 healthy dogs. They were receiving a booster at 10 months, so it’s still not quite a year of age. They started them on Zenrelia at either the label dose, three times the label dose, or placebo. They measured titers before, and then they vaccinated for distemper, parvovirus, hepatitis, and rabies, after being on Zenrelia for 28 days. Then, they measured titers two weeks later and a month after the vaccine.
What they found was that all dogs had a 100 % response, in all groups, to rabies, hepatitis and parvovirus. There was one dog in the placebo group and one dog who received three times the dose of Zenrelia, who did not have an adequate response to the distemper component of the vaccine.
[00:32:13] Dr. Lancellotti: Yeah. But for the most part, these dogs have responded really well, even at that three times dosing, and none of these animals had severe adverse effects or other infectious diseases, the way that happened in that original lab study design. This is very encouraging, to me, that in a real world setting, with animals who are closer to the population of animals that we are going to be treating, this drug is tolerated very well, and does not interfere with response to vaccination.
[00:32:45] Dr. Lewis: Exactly. Yeah. I was also encouraged to see this study.
[00:32:49] Dr. Lancellotti: Again, this is where the box warning on the label comes from. If you have questions, just follow up with your family veterinarian, to discuss the risk and the benefit, compared to some of the other medications that are out there.
Does Zenrelia Have Side Effects?
Dr. Lancellotti: What are some of the other risks that owners might want to be aware of? What would be unusual enough, to where the pet owner might want to reach out to their veterinarian?
[00:33:09] Dr. Lewis: Some of the side effects that we will occasionally see with Apoquel, I would expect that we will see with Zenrelia, because they are in the same class of drug. Occasionally, we will see weird infections like warts (which typically go away if we stop Apoquel, and I would presume with Zenrelia). We will occasionally see a white blood count that drops below normal level. That’s not very common, but we will occasionally see that with Apoquel. I would expect that’s something that we should be monitoring for patients who are on Zenrelia. Occasionally we’ll see dogs develop demodex. That was certainly seen in the very first Apoquel study because it was a higher dose. That’s also going to be potential side effect with Zenrelia.
Caregiver Burden in Owners of Allergic Dogs
Dr. Lewis: But I would also remind that we’re not using any of these drugs on a whim. These patients are suffering. They’re disrupting the bond between themselves and their pet parent, they’re not sleeping well at night, and it’s so important to have another tool in the toolbox, as you’ve already said. And I feel that this is an even bigger hammer. I have seen this drug work, when other drugs have failed. I have not seen a difference in side effects with this drug, compared to what we had with our other Janus kinase inhibitor drug. I’m excited to have it and use it, and I think I’m going to make a lot of my miserable patients better.
[00:34:37] Dr. Lancellotti: Yeah. I love having more options. The more things that I can reach for, and try to figure out what works for that individual animal, the better I can make them feel. This isn’t just a disease where the animal is suffering. The pet owners out there (our clients) who love these animals and see them suffering – they are experiencing caregiver burden. It is not uncommon for clients to come into my office and just break down with how frustrated they are, and how guilty they feel, over what their pet is going through. Having another way to help them is such a huge relief, and I really am excited about being able to offer another possible solution for the pets out there who are experiencing this disease.
[00:35:26] Dr. Lewis: I totally agree.
Zenrelia Decreases Inflammation and Infection From Allergies
[00:35:28] Dr. Lancellotti: You mentioned something, when you were talking about your cases that you had treated with Zenrelia – you talked about those secondary infections. This is really important for you and me, as dermatologists, and for medical professionals out there who witness (firsthand) the effects of multi-drug resistant infections. Secondary infections are very common in these allergic animals, and that’s the result of the inflammation from the disease causing damage to the protective functions of the skin, which leads to normal bacteria and yeast causing infections. You can learn more about secondary infections on the skin and in the ears with doctors Alicia Webb Milum and Dr. Meagan Painter, who give great explanation about these types of infections and what to do about them.
If we can get their itch and inflammation to more normal levels, we will be able to dramatically slow the use of antibiotics to treat these infections, and help to slow the development of multi-drug resistant infections. What happens within our patients in the veterinary world also has an effect on what’s happening in the humans that we treat. We don’t want to have multi-drug resistant infections in humans either, so having an option that helps to control the primary disease and the inflammation allows us to minimize the amount of antibiotics. I’m really excited about that aspect of a new therapy.
[00:36:59] Dr. Lewis: And it’s a good point. The one study that looked at dogs with atopic dermatitis, we significantly improved inflammation. We’ve talked a lot about stopping itch, which is good, but it’s even better that we reduce the inflammation, as well.
[00:37:14] Dr. Lancellotti: Yeah. That’s great.
Closing Thoughts on Zenrelia
Dr. Lancellotti: So do you have any big takeaway points that you want pet owners to remember?
[00:37:20] Dr. Lewis: I would say that if your pet is not comfortable, if that itch is out of control, if the bond is being strained, if you’re feeling burdened or overwhelmed with management, or the expense of multiple therapies (we haven’t even touched on that, but this is going to be priced competitively, and for some of the patients that I have that are requiring multiple therapies), this will be cost saving as well. So that’s exciting to me. The fact that we have controlled the inflammation, and that patients don’t have to be bathed twice a week, is probably going to excite a lot of my clients. So those are my big takeaways.
[00:38:02] Dr. Lancellotti: Yeah. I think it’s exciting to see how this folds into our dermatology practice, and where we can put it to good use. But there are a lot of things that go on with patients with allergies, so if you are a pet owner out there listening, and you have an allergic pet, there are a lot of great episodes that help to explain flea allergies, food allergies, and environmental allergies, at the very beginning of this podcast series. Also, you can check out the ‘find a specialist’ link on the website, to see if there’s a veterinary dermatologist near you. This is something that we feel really passionately about. We spend our free time reading journals and talking with each other about cases, and we’re a really good resource, so if there’s a veterinary dermatologist in your area, you can find one on the website. There’s a link in the show notes there.
Dermatology for Animals Across the United States
Dr. Lancellotti: Dr. Lewis, if we’ve got some folks from Arizona listening who might want to come consult with you, where might they find your practice?
[00:39:12] Dr. Lewis: I’m in Gilbert, Arizona, and my company is Dermatology for Animals. If you want to go see one of those 23 residents that I talked about, we have locations scattered throughout the United States, partly because I trained them in Arizona and then they wanted to move to Akron, or New York, or New Mexico. So, you can find all of that on our website.
[00:39:37] Dr. Lancellotti: Great. I’ll have a link to the website in the show notes, for those owners that want to see where Dr. Lewis practices or reach out to any of the dermatologists at Dermatology for Animals.
Scratching the Itch - Merlin App
Dr. Lancellotti: I like to end each episode with a segment called Scratching The Itch. This is a segment that highlights something, whether it’s a human interest story, a product, a website, etc. It’s just something that provides relief or makes you feel good. Hence, scratching the itch. Dr. Lewis, from having many conversations with you, I know that you are an avid “birder.” You love seeing different birds out in the wild, going on vacations, and exploring the native bird populations there. I imagine that your ‘scratching the itch’ is going to have something to do with your bird watching. Can you tell our listeners about that, please?
[00:40:23] Dr. Lewis: Maybe it’s a little bit of a disease, but I do enjoy watching birds and they give me great joy. There are a lot of people who get great joy, and there are also a lot of people who are casual – they just like looking at the birds out the window. But there’s free app called Merlin, which is the name of a falcon actually. Merlin app is free to download and it’s an amazing app because of a feature called sound ID. You hit the icon, you hit the microphone, and it can listen, recognize, and identify most birds. It’s not foolproof. You will sometimes get a misreading on Merlin, but overall, it’s a great tool. I literally used it this morning. Before this recording, I was hearing some things outside, and while I knew most of them, there was one bird I heard that I just wasn’t quite sure about, and Merlin picked it up. It was Verdin. And I said, “Oh yes, of course, that’s a Verdin.”
[00:41:23] Dr. Lancellotti: That’s awesome. My mom uses this app on a very regular basis. I think anytime she comes to visit us, or we go on vacation with her somewhere, she’s pulling it out to see what the native bird species are. It’s a really fun, cool app. The kids like it. And there are a lot of really good resources on there to play around with. I’ll have a link to the Merlin app, on the show notes, if you want to check that out.
[00:41:45] Dr. Lewis: And if you have any citizen science drive in you, you can pair it with eBird, which is really a worldwide collection of bird data, and is actually very helpful in monitoring bird populations. Any finding you put into eBird, it will link to your life list on Merlin.
[00:42:04] Dr. Lancellotti: Oh, that’s awesome. So you can be a little bit of backyard scientist and help the science community out there with your findings. That’s really cool. Dr. Lewis, thank you so much for coming on and sharing your experience and the information. And thank you for everything that you do for veterinary dermatology. This profession would not be the same without folks like you and the people that have really dedicated themselves to the itchy, scratchy pets out there. I appreciate your time and expertise.
[00:42:33] Dr. Lewis: Well, those are very kind words. Thank you. But I also have to say that this next generation, like yourself, I’m just overwhelmed and blown away with what you’ve done with this podcast and the information that you’re getting out there to clients. I am totally impressed.
[00:42:51] Dr. Lancellotti: Well, thank you. That means a lot. I really appreciate that. And thank you to everybody who’s listening. I look forward to your next visit with Your Vet Wants You to Know.
