A Study to Evaluate the Safety, Pharmacokinetics, and Occurrence of Anti-Drug Antibodies Followin… (NCT07225959) | Clinical Trial Compass
Active — Not RecruitingPhase 2
A Study to Evaluate the Safety, Pharmacokinetics, and Occurrence of Anti-Drug Antibodies Following Annual Doses of CD388
United States, United Kingdom400 participantsStarted 2025-10-29
Plain-language summary
The goal of this clinical study is to learn if giving repeated annual doses of the experimental drug CD388 is safe and how the body reacts to it in healthy adults who have already received one dose without serious side effects. The study aims to determine if the body makes antibodies against CD388 after repeated doses, which might affect how the drug works or how safe it is, and to better understand the safety and tolerability of repeated doses. Participants will receive two doses of CD388 over two years and be monitored for 18 months. Researchers will check for immune responses against the drug, watch for any side effects, and measure how the drug behaves in the body over time. This study is based on the idea that people who tolerated CD388 well before will likely continue to tolerate it safely with repeated annual dosing, and that the risk of immune reactions will remain low. Expanded access to the study drug will not be provided to participants after the study ends.
Who can participate
Age range
18 Years – 66 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Be willing and able to provide written informed consent and comply with scheduled visits, laboratory tests, and other study procedures.
. Be a male or female adult aged 18 to 66 years of age who previously completed participation in Study CD388.SQ.2.05, having received a SQ CD388 dose of either 150 mg, 300 mg or 450 mg. (Note: Participants in this study may have received seasonal influenza vaccine prior to enrollment in this study and may receive influenza vaccine during this study, with certain exceptions as described in the protocol.)
. Be in stable health at the time of screening and enrollment (in the Investigator's clinical judgment). Participants may not have a history of underlying hematologic, oncologic, renal, autoimmune, cardiac, or pulmonary conditions; or be considered at risk of developing complications from influenza infection per the United States Centers for Disease Control and Prevention (CDC) guidelines (chronic obstructive pulmonary disease \[COPD\], asthma, current immune-compromised cancer \[except non-melanomatous skin cancer\], or diabetes). Study participants will be included based on medical history and vital signs obtained during the screening process.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Occurrence of Anti-Drug Antibodies (ADAs) in Participants Administered CD388
Timeframe: On Day 1 (pre-dose baseline), Day 29, Day 85, Day 169, and Day 197 in Study Period 1; on Day 1 (pre-dose), Day 29, Day 85, Day 169, and Day 197/End of Study (EOS) in Study Period 2
Trial details
NCT IDNCT07225959
SponsorCidara Therapeutics Inc., a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA)
. Have a body mass index (BMI; calculated as weight in kilograms \[kg\] divided by height in meters \[m\] squared)) of ≥18 kg/m\^2.
. Must agree to the following contraception requirements:
. Must agree not to donate blood from Day 1 until 40 weeks after each administration of CD388.
. Must be able to read, understand, and complete protocol questionnaires using the Sponsor-designated diary mode (eDiary or paper) and language, and be willing and able to adhere to the prohibitions and restrictions specified in this protocol. If eDiary is designated, the participant must be able to use a smartphone/tablet/computer. If an appropriate language version is not available in either eDiary or paper, the participant must not be enrolled. The diary mode and approved languages will be designated by the Sponsor prior to study start.
. Must be willing to provide verifiable identification, has means to be contacted, and is able to contact the Investigator/study site and communicate reliably during participation in this study.
Exclusion criteria
. Have a known or suspected allergy or history of anaphylaxis or other serious adverse reactions to zanamivir (following administration of inhaled or intravenous formulations), monoclonal antibodies (including crystallizable fragment \[Fc\] domains), or any of the components of CD388.
. Have an acute illness (including acute respiratory illnesses) or body temperature ≥38.0 degrees Celsius (ºC) (≥100.4 degrees Fahrenheit \[ºF\]) within 7 days prior to each administration of CD388. (Note: Enrollment and/or receipt of study intervention at a later date, subsequent to resolution of the illness \[within the screening period\], is permitted.)
. Have a serious and/or clinically unstable condition, including but not limited to, a psychiatric condition including recent (within the past year) or active suicidal ideation/behavior, Alzheimer's disease, or any other condition which in the opinion of the Investigator might lead to hospitalization or death within this study period and for which enrollment would not be in the participant's best interest, or could prevent, confound, or limit the protocol-specified assessments.
. Have any history of alcohol or substance abuse which in the opinion of the Investigator might interfere with conduct of this study as planned.
. Had major surgery (e.g., cardiac, pulmonary, neurologic, or abdominal operations) within 4 weeks prior to screening, or will not have fully recovered from such prior surgery; or has major surgery planned during the time the participant is expected to participate in this study.
. Had screening electrocardiogram (ECG) findings of prolonged QT interval corrected using Fridericia's formula (QTcF) (greater than 450 milliseconds \[msec\] in males or greater than 470 msec in females), prolonged PR interval (greater than 220 msec), second- or third-degree heart block, or other clinically significant dysrhythmia.
. Have any finding (at the time of screening) that may significantly increase the risk of participation in this study, affect the ability to participate in this study, or impair interpretation of the study data.
. Have current or planned participation in another clinical study where study intervention is being administered while participating in this current study. Note: Concurrent enrollment is allowed during the follow-up phase of the other clinical study or in case the study intervention in the other clinical study is a marketed product already approved for another indication - exception being if the other study requires study interventions that could affect the safety assessments of this present study (e.g., clinical laboratory tests).