The Use of Penicillin Allergy Clinical Decision Rule to Enable Direct Oral Penicillin Challenge (PALACE)
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ClinicalTrials.gov Identifier: NCT04454229 |
Recruitment Status :
Completed
First Posted : July 1, 2020
Last Update Posted : March 6, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Hypersensitivity, Immediate Hypersensitivity, Delayed Hypersensitivity Response | Other: Direct oral penicillin challenge Other: Standard of care | Not Applicable |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 382 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | Direct oral challenge in patients with PEN-Fast less than 3 Eligible patients referred to the outpatient clinic reporting a penicillin allergy will be identified and assessed with a standard clinical history and the calculation of the PEN-FAST score. PEN-FAST is a three-point clinical assessment tool recently externally validated in a multicenter study, with a PEN-FAST score of < 3 associated with 96.7% negative predictive value. Intervention: The patient will receive a single dose of oral penicillin, following baseline vital signs (i.e. temperature, heart rate, blood pressure, respiratory rate, skin check). Nursing staff will repeat vital signs as needed and after oral challenge while observing for signs of an immune mediated adverse reaction. If at any stage an antibiotic associated adverse event is noted, standard of care treatment is offered by the attending clinicians (ex. adrenalin for immediate hypersensitivity reaction). |
Masking: | None (Open Label) |
Primary Purpose: | Diagnostic |
Official Title: | The Use of Penicillin Allergy Clinical Decision Rule to Enable Direct Oral Penicillin Challenge - An International Multicenter Randomized Control Trial - The PALACE Study |
Actual Study Start Date : | July 1, 2021 |
Actual Primary Completion Date : | December 2, 2022 |
Actual Study Completion Date : | December 2, 2022 |

Arm | Intervention/treatment |
---|---|
Experimental: Direct oral antibiotic challenge
Direct oral antibiotic (penicillin) challenge in patients with PEN-Fast less than 3.
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Other: Direct oral penicillin challenge
The patient will receive a single dose of oral penicillin, following baseline vital signs. |
Active Comparator: Standard of care
Standard of care: skin testing and, if negative, oral challenge.
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Other: Standard of care
Routine management as per the treating clinicians that include skin prick and intradermal beta-lactam testing, followed by oral penicillin challenge in the setting of negative skin testing. |
- The difference in the proportion of positive oral challenges (i.e. immune-mediated reaction) [ Time Frame: up to 48H after oral challenge ]
- Proportion of patients referred to the outpatient allergy clinic that are eligible for intervention (i.e randomization) as per protocol [Eligibility to screened ratio] [ Time Frame: Before randomization ]
- Feasibility of recruitment defined as the proportion of patients consenting to participate in the study as per protocol from eligible patients. [Recruitment to eligibility ratio]. [ Time Frame: Before randomization ]
- Feasibility of intervention delivery defined as the proportion of patients randomized to the intervention arm who had the intervention delivered as per protocol. [Intervention to recruitment ratio] [ Time Frame: Before randomization ]
- The proportion of patients with a penicillin allergy who experience an antibiotic associated immune mediated adverse event OR severe adverse drug reaction as per protocol definitions. [ Time Frame: Up to 48h after the drug challenge ]
- The proportion of patients with a penicillin allergy who experience an antibiotic associated non-immune mediated adverse event. [ Time Frame: Up to 48h after the drug challenge ]
- The proportion of patients that will respect the protocol (protocol compliance) [ Time Frame: Up to 48h after the drug challenge ]
- Proportion of patient with positive Penicillin Skin Testing [ Time Frame: Up to 48h after the drug challenge ]
- Proportion of patients with non-immune mediated positive oral provocation [ Time Frame: Up to 48h after the drug challenge ]
- Proportion of patients with severe adverse reaction - anaphylaxis/death [ Time Frame: Up to 48h after the drug challenge ]
- Time from randomization to delabelling [ Time Frame: Up to 48h after the drug challenge ]
- Number of appointments required for Penicillin delabelling [ Time Frame: Up to 48h after the drug challenge ]
- Assessment with the Pre-Questionnaire and the 6 months follow-up Questionnaire [ Time Frame: Up to 6 months after the drug challenge ]

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Adult patients referred to the outpatient allergy clinic for a penicillin allergy history;
- Willing and able to give consent.
Exclusion Criteria:
- Patient age is < 18 years;
- Patients with a PEN-FAST score less than 3
- Pregnancy;
- Any other illness that, in the investigator's judgement, will substantially increase the risk associated with subject's participation in this study;
- Patients with history of type A adverse drug reaction, drug-associated anaphylaxis, idiopathic urticaria/anaphylaxis, mastocytosis, serum sickness, blistering skin eruption or acute interstitial nephritis;
- Patients where the allergy history was not able to be confirmed with patient;
- Patients on concurrent antihistamine therapy;
- Patients receiving more than stress dose steroids (i.e. > 50mg QID hydrocortisone [or steroid equivalent]).

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04454229
United States, North Carolina | |
Duke University Medical Center | |
Durham, North Carolina, United States, 27710 | |
United States, Tennessee | |
Vanderbilt University Medical Center | |
Nashville, Tennessee, United States, 37232 | |
Australia, Victoria | |
Austin Health | |
Heidelberg, Victoria, Australia, 3084 | |
Peter MacCallum Cancer Center | |
Melbourne, Victoria, Australia, 3000 | |
Royal Melbourne Hospital | |
Melbourne, Victoria, Australia, 3000 | |
Canada, Quebec | |
McGill University Health Centre (MUHC) | |
Montreal, Quebec, Canada, H3G 1A4 |
Documents provided by Ana Copaescu, McGill University Health Centre/Research Institute of the McGill University Health Centre:
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Ana Copaescu, Physician-Scientist Immunology and Allergy, McGill University Health Centre/Research Institute of the McGill University Health Centre |
ClinicalTrials.gov Identifier: | NCT04454229 |
Other Study ID Numbers: |
PALACE1 |
First Posted: | July 1, 2020 Key Record Dates |
Last Update Posted: | March 6, 2023 |
Last Verified: | March 2023 |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Product Manufactured in and Exported from the U.S.: | No |
penicillin Low Risk allergy direct oral challenge standard of care outpatient clinic |
Hypersensitivity Hypersensitivity, Immediate Hypersensitivity, Delayed Immune System Diseases |
Penicillins Anti-Bacterial Agents Anti-Infective Agents |