Published Data Shows that the Active Ingredient, Lotilaner, in Credelio Quattro:

• Kills existing black-legged tick (Ixodes scapularis) infestations faster² than leading competitors, within just 8 hours of treatment.ⁱ
• Kills the lone star tick (Amblyomma americanum) within 12 hours of infestation; achieving the fastest³ initial speed of tick kill compared to the competition.ⁱⁱ
• Achieves a rapid speed of kill⁴ on Day 0 and on Day 28, with no statistically significant drop-off in performance at the end of the dosing period.^i,ii
• Outlasts competitors whose speed of kill^2,4 performance declined at the end of the month.^i,ii

INDIANAPOLIS, July 22, 2026 /PRNewswire/ -- When it comes to killing ticks, veterinarians and pet owners want it done fast. New data published in Parasites & Vectors, a leading peer-reviewed publication, demonstrates that Elanco Animal Health's (NYSE: ELAN) Credelio Quattro™ (lotilaner, moxidectin, praziquantel, and pyrantel chewable tablets) kills ticks¹ faster² than leading competitors Simparica Trio^® (sarolaner, moxidectin, and pyrantel chewable tablets) and NexGard^® Plus (afoxolaner, moxidectin, and pyrantel chewable tablets).ⁱ

Newly Published Data Found Credelio Quattro:

• Faster² Tick¹ Speed of Kill: Credelio Quattro is the only product proven to significantly reduce black-legged ticks within 8 hours.ⁱ  Lotilaner, the active ingredient in Credelio Quattro also has the fastest initial tick speed of kill against the lone star tick - in just 12 hours – and sustains the advantage throughout the dosing interval.ⁱⁱ
• Outperforms the Competition: Outperforms Simparica Trio^® (12 hours) and NexGard^® Plus (24 hours) at the end of the dosing period (Day 28).ⁱ
• Consistency Over Competitors: Achieves 8-hour speed of kill¹ on Day 0 and on Day 28 with no performance drop-off. Rapid kill is critical for preventing Lyme disease transmission, which typically occurs 24-48 hours after attachment.ⁱ

"Speed of kill is a critical factor for veterinarians and pet owners when choosing parasite coverage because the longer a tick is attached, the more likely it is to transmit dangerous diseases, like Lyme disease, to pets," said Dr. Casey Locklear, veterinarian and leading parasiticides expert at Elanco. "These results reinforce that lotilaner, the active ingredient in Credelio Quattro, not only starts working fast but maintains its speed of kill⁴ against multiple species of ticks⁵, providing veterinarians and pet owners with the confidence that their dogs are protected from the very start of the month to the very end."

The black-legged tick is the primary vector for Borrelia burgdorferi, the bacterium responsible for Lyme disease and anaplasmosis. The study, which evaluated the speed of kill against Ixodes scapularis (black-legged tick), found that Credelio Quattro was the only product tested to achieve significant initial tick reduction² within just 8 hours of infestation. Notably, this rapid speed of kill¹ was maintained from the beginning of the month through Day 28, providing consistent protection for the entire dosing interval.ⁱ

"Ticks are on the move. They are no longer limited to the places or seasons where we have historically expected to find them," said Dr. Kathryn Reif, Bailey-Goodwin Endowed Associate Professor in Parasitology at Auburn University. "As their geographic range expands, so does the risk of tick bites and exposure to the pathogens they carry. Because tick-borne diseases can threaten the health of people, pets, and livestock, raising public awareness is more important than ever as tick populations grow and spread into new regions."

The findings are based on evaluation time points at 4, 8, 12, 24, and 48 hours post-treatment and reinfestation. The data demonstrates that Credelio Quattro outperforms Simparica Trio and NexGard Plus in rapid tick¹ reduction, particularly in the critical first 8 to 12 hours.ⁱ

Credelio Quattro also has a U.S. Food and Drug Administration approved claim for prevention of Lyme disease in dogs as a direct result of killing black-legged ticks.

Does Credelio Quattro Kill the Lone Star Tick?

Credelio Quattro is approved to protect dogs from the lone star tick (Amblyomma americanum), and its active ingredient, lotilaner, also has the fastest³ initial speed of tick kill against the lone star tick – in just 12 hours – and sustains that advantage throughout the dosing interval.ⁱⁱ This aggressive and expanding tick species – established across the South, Midwest and Northeast, and continuing to spread –  is one of the hardest to kill and is best known for its association with alpha-gal syndrome, or the red meat allergy in humans. It can also transmit dangerous disease-causing pathogens to dogs.ⁱⁱⁱ A 2024 head-to-head study published in Parasites & Vectors compared lotilaner, the active ingredient in Credelio (lotilaner) and Credelio Quattro with sarolaner in Simparica Trio and afoxolaner in NexGard^®, and found that lotilaner kills the lone star tick faster⁴ than sarolaner in Simparica Trio and afoxolaner in NexGard, protecting dogs against this pathogen-carrying tick.  

"With a heavier tick season and emergency room visits from tick bites on the rise^iv, pet owners should remain vigilant and keep their pets on year-round parasite coverage," Dr. Locklear notes. "We continue to look for opportunities to make parasite protection stronger and evolve research around best-in-class medicines."

Frequently Asked Questions About Ticks and Credelio Quattro:

How fast does Credelio Quattro kill ticks? 

Studies show that lotilaner, the active ingredient in Credelio Quattro kills ticks⁵  faster⁶ than the competition.^i,ii A 2026 study published in Parasites & Vectors shows that Credelio Quattro achieved significant reduction² of black-legged ticks within 8 hours of infestation.ⁱ A 2024 study shows that lotilaner, the active ingredient in Credelio and Credelio Quattro also has the fastest³ initial speed of tick kill against the lone star tick – in just 12 hours – and sustains that advantage throughout the dosing interval.ⁱⁱ

Why is it important to kill ticks quickly?

The risk of disease transmission increases the longer a tick remains attached, making rapid speed of kill a critical factor in preventing the transmission of disease. A 2026 study shows that Credelio Quattro was the only product tested that significantly reduced² black-legged ticks within 8 hours.ⁱ

Does Credelio Quattro lose effectiveness to kill ticks¹ quickly at the end of the month? 

No. The data shows that Credelio Quattro maintains its 8-hour speed of kill² on Day 28, whereas competitors showed a decline in performance.ⁱ

Are black-legged ticks linked to the red meat allergy in humans?

In the United States, alpha-gal syndrome, or red meat allergy, is usually associated with bites from the lone star tick (Amblyomma americanum); however, two Emerging Infectious Diseases studies link bites from black-legged ticks (deer ticks) and western black-legged ticks to potentially life-threatening alpha-gal syndrome.^v Additional work will be needed to determine a possible link, according to the researchers, but this continues to put emphasis on the need for tick bite protection for humans.

To learn more about Credelio Quattro visit CredelioQuattroVet.com.

PM-US-26-1188

1. Ixodes scapularis (black-legged tick)
2. Based on the time to statistical significance vs. control in a head-to-head study on Day 0 post-treatment and Day 28 for reinfestations comparing Credelio Quattro, which contains lotilaner as well as moxidectin, praziquantel, and pyrantel—to the active ingredients in Simparica Trio (sarolaner, moxidectin, and pyrantel) and NexGard Plus (afoxolaner, moxidectin, and pyrantel) against Ixodes scapularis.
3. Based on the time to statistical significance vs. control in a head-to-head study comparing Credelio (lotilaner)—not Credelio Quattro, which contains lotilaner as well as moxidectin, praziquantel, and pyrantel—to the active ingredients in Simparica Trio (sarolaner, moxidectin, and pyrantel) and NexGard (afoxolaner). 
4. Based on the time to statistical significance vs control in two separate head-to-head studies. The first study compared Credelio (lotilaner)—not Credelio Quattro, which contains lotilaner as well as moxidectin, praziquantel, and pyrantel—to the active ingredients in Simparica Trio (sarolaner, moxidectin, and pyrantel) and NexGard (afoxolaner) against Amblyomma americanum. The second study compared Credelio Quattro, which contains lotilaner as well as moxidectin, praziquantel, and pyrantel—to the active ingredients in Simparica Trio (sarolaner, moxidectin, and pyrantel) and NexGard Plus (afoxolaner, moxidectin, and pyrantel) against I. scapularis.
5. Ixodes scapularis (black-legged tick) and Amblyomma americanum (lone star tick)

NexGard and NexGard Plus are registered trademarks of Boehringer Ingelheim Animal Health USA Inc. Simparica Trio is a registered trademark of Zoetis Services LLC.

Credelio Quattro, Credelio, Elanco and the diagonal bar logo are trademarks of Elanco or its affiliates. Other company and product names are trademarks of their respective owners. © 2026 Elanco or its affiliates

ABOUT ELANCO
Elanco Animal Health Incorporated (NYSE: ELAN) is a global leader in animal health dedicated to innovating and delivering products and services to prevent and treat disease in farm animals and pets, creating value for farmers, pet owners, veterinarians, stakeholders and society as a whole. With 70 years of animal health heritage, we are committed to breaking boundaries and going beyond to help our customers improve the health of animals in their care, while also making a meaningful impact on our local and global communities. At Elanco, we are driven by our vision of Food and Companionship Enriching Life and our purpose – all to Go Beyond for Animals, Customers, Society and Our People. Learn more at www.elanco.com.

Indications for Credelio Quattro/Credelio Quattro-CA1

Credelio Quattro is indicated for the prevention of heartworm disease and the treatment and control of roundworm, hookworm, and tapeworm infections. Credelio Quattro kills adult fleas and is indicated for the treatment and prevention of flea infestations and the treatment and control of tick infestations for 1 month in dogs and puppies 8 weeks of age and older and weighing 3.3 pounds or greater. Credelio Quattro is indicated for the prevention of Lyme disease infections as a direct result of killing black-legged ticks.

Credelio Quattro-CA1 is conditionally approved for the treatment of infestations caused by New World screwworm (NWS) larvae in dogs and puppies 8 weeks of age and older and weighing 3.3 pounds or greater.

Important Safety Information for Credelio Quattro/Credelio Quattro-CA1

Lotilaner, an ingredient in Credelio Quattro/Credelio Quattro-CA1, belongs to the isoxazoline class and has been associated with neurologic adverse reactions like tremors, incoordination, and seizures even in dogs without a history of seizures. Use with caution in dogs with a history of seizures or neurologic disorders. Dogs should be tested for existing heartworm infections before Credelio Quattro/Credelio Quattro-CA1 administration as it is not effective against adult heartworms. The safe use in breeding, pregnant, or lactating dogs has not been evaluated. The most frequently reported adverse reactions in clinical trials were vomiting and diarrhea.

Credelio Quattro-CA1 is conditionally approved by the FDA pending a full demonstration of effectiveness under application number 141-619. If you suspect that your dog is infested with NWS larvae, seek veterinary care immediately for treatment to include removal of larvae and appropriate wound care.

For complete safety information, please see the Credelio Quattro/Credelio Quattro-CA1 product label or ask your veterinarian.

Indications for Credelio
Credelio kills adult fleas and is indicated for the treatment and prevention of flea infestations and treatment and control of tick infestations (lone star tick, American dog tick, black-legged tick, brown dog tick, and longhorned tick) for one month in dogs and puppies 8 weeks and older and 4.4 pounds or greater. Credelio is indicated for the prevention of Lyme disease infections as a direct result of killing black-legged ticks.

Important Safety Information for Credelio
Lotilaner is a member of the isoxazoline class of drugs. This class has been associated with neurologic adverse reactions including tremors, incoordination, and seizures. Seizures have been reported in dogs receiving this class of drugs, even in dogs without a history of seizures. Use with caution in dogs with a history of seizures or neurologic disorders. The safe use of Credelio in breeding, pregnant or lactating dogs has not been evaluated. The most frequently reported adverse reactions are weight loss, elevated blood urea nitrogen, increased urination, and diarrhea. For complete safety information, please see Credelio product label or ask your veterinarian.

ⁱ Reif, K.E., Kollasch, T.M., Locklear, C.L. et al. Comparative speed of kill of induced Ixodes scapularis infestations following treatment of dogs with endectocides containing either sarolaner (Simparica Trio™), afoxolaner (NexGard^® PLUS), or lotilaner (Credelio Quattro™). Parasites Vectors (2026). https://doi.org/10.1186/s13071-026-07559-y
ⁱⁱ  Reif KE, Kollasch TM, Neilson JC, Herrin BH, Ryan WG, Bell MC, Beltz MS, Dryden MW, Jesudoss Chelladurai JRJ, Miller KR, Sutherland CJ. Comparative speed of kill provided by lotilaner (Credelio™), sarolaner (Simparica Trio™), and afoxolaner (NexGard™) to control Amblyomma americanum infestations on dogs. Parasite Vectors. 2024 Jul 20;17(1):313.
ⁱⁱⁱ Centers for Disease Control and Prevention. (n.d.). Where Ticks Live. Centers for Disease Control and Prevention. Retrieved August 8, 2024, from https://www.cdc.gov/ticks/about/where-ticks-live.html
^iv CDC Data Show Weekly ER Visits for Tick Bites Higher Than Usual." Centers for Disease Control and Prevention, 23 Apr. 2026,
^v Van Beusekom, Mary. "Research Ties Bites from 2 More Types of Ticks to Red Meat Allergy." CIDRAP (Center for Infectious Disease Research and Policy), 4 Apr. 2025

Investor Contact: Tiffany Kanaga (765) 740-0314 tiffany.kanaga@elancoah.com
Media Contact: Season Solorio (765) 316-0233 season.solorio@elancoah.com

View original content to download multimedia:https://www.prnewswire.com/news-releases/credelio-quattro-lotilaner-moxidectin-praziquantel-and-pyrantel-chewable-tablets-kills-ticks-faster-than-simparica-trio-sarolaner-moxidectin-and-pyrantel-chewable-tablets-and-nexgard-plus-afoxolaner-moxidectin-and-302831444.html

SOURCE Elanco Animal Health