Recruiting
Phase 1
Phase 2

Tick Bite Response

Sponsor:

National Institute of Allergy and Infectious Diseases (NIAID)

Code:

NCT05036707

Conditions

Tick-borne Diseases

Tick Resistance

Lyme Disease

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Interventions

Xenodiagnosis Ticks

skin biopsy

blood draw

Study Details

Brief summary:

Background:

Each year, the number of cases of tick-borne diseases increases. The deer tick (Ixodes scapularis) is the vector of at least 7 pathogens that cause human diseases, including Lyme disease. Researchers want to learn more to help them develop vaccines against ticks in the future.

Objective:

To learn how people s bodies, particularly the skin, respond to tick bites.

Eligibility:

Healthy adults aged 18 years and older who have no known history of a tick-borne disease or tick bite exposure.

Design:

Participants will be screened with a medical history, physical exam, and blood tests.

Participants will have 2 skin punch biopsies of healthy skin. For this, a sharp instrument will be used to remove a round plug of skin about the size of a pencil eraser. Participants will then have 10 clean laboratory-bred ticks placed at 2 different sites on their skin (20 ticks total). The ticks will be removed from the first site 1 day after placement and from the second site 2-4 days after placement. Participants will complete symptom diary cards. They will answer questions about itching at the tick feeding sites. They will give blood samples. Photos will be taken of the tick feeding sites. Skin punch biopsies will be collected at the sites of the tick bites.

Participants will repeat the tick feeding procedures 2 times, each 2-8 weeks apart. For the 2nd and 3rd procedures, 10 clean laboratory-bred ticks will be placed at 1 site. The ticks will be removed 2-3 days after tick placement. They will have telephone follow-up visits after each procedure.

After the final tick removal, participants will have follow-up visits in 4-6 weeks and again in 3 months. They will give blood samples and discuss how they are feeling.

Participation will last about 5-7 months.

Conditions

Tick-borne Diseases

Tick Resistance

Lyme Disease

Study ID

NCT05036707

Start date

Feb 28, 2022

Status verified date

May 4, 2026

Completion date

Jun 30, 2028

Anticipated

Primary completion date

Jun 30, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

  • INCLUSION CRITERIA:

In order to be eligible to participate in this study, an individual must meet all of the following criteria:

1. Stated willingness to comply with all study procedures and availability for the duration of the study.
2. Age 18 years or older.
3. In good general health as evidenced by medical history.
4. No history of TBD.
5. No known tick bite.
6. Serum IgE level within Clinical Center Department of Laboratory Medicine normal range.

https://ccinternal2.cc.nih.gov/LTGRA/UL/public\_labtest\_detail.aspx?next\_flg=Y\&test\_id=4731\&id\_order=53
7. Serum tryptase level within Clinical Center Department of Laboratory Medicine normal range.

https://ccinternal2.cc.nih.gov/LTGRA/UL/public\_labtest\_detail.aspx?next\_flg=Y\&test\_id=1157\&id\_order=1
8. For participants of child-bearing potential: use of effective contraception for at least 1 month prior to tick placement, and agreement to use such a method during study participation and for an additional 3 months after the removal of the last ticks. Types of contraception include abstinence, surgical methods (sterilization, implants, intrauterine device, partner with vasectomy), hormonal methods (birth control pill, patch, ring, injection), or barrier methods (diaphragm plus spermicide, male condom plus spermicide)
9. For males of reproductive potential: use of condoms or other methods to ensure effective contraception with partner.
10. Agree to not participate in other clinical studies requiring investigational interventions for the duration of the study.
11. Minimum hemoglobin of 13.0 g/dL for males and 12 g/dL for females

EXCLUSION CRITERIA:

An individual who meets any of the following criteria will be excluded from participation in this study:

1. History of forming large thick scars (keloids) after skin injuries.
2. History of excessive bleeding after cuts or procedures.
3. History of taking anticoagulants in the past 28 days.
4. History of allergic reaction to lidocaine.
5. History of allergic reaction to tape, adhesive bandages, or dressings.
6. Inability to maintain the dressing for any reason.
7. Pregnancy or lactation.
8. Treatment with another investigational drug or other intervention within the past 30 days.
9. Oral or intravenous (IV) steroids in the 2 weeks prior to each tick placement procedure (topical, nasal, inhaled, intra-articular, and replacement doses of steroids are not exclusions).
10. History of reactions to mammalian meat, IgE- mediated food allergies, urticaria or anaphylaxis. Mild pollen-food allergy syndrome is not an exclusion.
11. History of systemic allergic reaction to venom (bee, wasps and other Hymenoptera stings).
12. History of clinically significant drug allergies.
13. History of moderate to severe atopy asthma, atopic dermatitis, allergic rhinitis.
14. Active severe skin disease, uncontrolled diabetes, cancer other than non-melanoma skin cancers, autoimmune disease requiring immunosuppressive therapy, or history of human immunodeficiency virus (HIV), chronic viral hepatitis, or syphilis.
15. Refusal to allow storage of samples and data for future usage..
16. Any other condition that, in the opinion of the investigator, would make the patient unsuitable for enrollment or could interfere with the patient participating in and completing the study.

Exclusion of Select Populations:

Children:

Children are excluded from this protocol as there is no direct benefit to the participants, the risk from the skin biopsies is small but above minimal, the procedure is invasive and can be stressful for children, and there is concern over their ability to maintain the LeFlap dressing.

Pregnant and breastfeeding women:

Pregnant and breastfeeding women are excluded from trial participation as there is no direct benefit to the participants.

Adults who lack capacity to consent:

Adults lacking decision-making capacity to provide informed consent are excluded at screening as there is no direct benefit to the participants.

Enrolled participants who permanently lose the ability to consent during participation will be monitored for safety but will have no additional research procedures performed.

Study Design

Enrollment

60 participants

Anticipated

Intervention Model

Single group

Primary purpose

Diagnostic

Interventions and Outcome Measures

Arms

active comparator: 1

Healthy Volunteer

Interventions

Xenodiagnosis Ticks

Larval ticks will be obtained from Dr. Sam Telford from a laboratory maintained tick colony at Tufts Veterinary School. These ticks are hatched from eggs laid by ticks that have fed only on specific pathogen free laboratory animals that were purchased from established vendors.

skin biopsy

2-3 mm skin punch biopsies will be performed.

blood draw

Peripheral blood draws will be performed.

Primary outcome measure

  • Assessment of Safety of the device. Use toxicity tables and safety monitoring as specified in the protocol. [ Time Frame: continuous ]
  • Develop a model of acquired tick resistance in humans. Use validated pruritus scales, numerical rating system, verbal rating system, and visual analogue system. [ Time Frame: end of study ]

Central Contacts and Locations

Central contacts

Locations

National Institutes of Health Clinical Center

Recruiting

Bethesda, Maryland, United States, 20892

Contacts

For more information at the NIH Clinical Center contact Office of Patient Recruitment (OPR)

800-411-1222prpl@cc.nih.gov

More Information

Sponsor

National Institute of Allergy and Infectious Diseases (NIAID)

Last update posted

May 6, 2026

Last verified

May 4, 2026

Keywords

  • Tick Immunity
  • Tick-borne diseases
  • Vaccines
  • Lyme Disease

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by National Institute of Allergy and Infectious Diseases (NIAID) on 2026-05-06.