Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT04397445 |
Other study ID # |
SCR-010 |
Secondary ID |
|
Status |
Completed |
Phase |
Phase 1
|
First received |
|
Last updated |
|
Start date |
June 8, 2020 |
Est. completion date |
July 1, 2020 |
Study information
Verified date |
August 2021 |
Source |
Food and Drug Administration (FDA) |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Ranitidine is an over-the-counter and prescription drug, which decreases the amount of acid
secreted by the stomach. Some ranitidine medicines contain an impurity called
N-nitrosodimethylamine (NDMA) at low levels. NDMA is classified as a probable human
carcinogen (a substance that could cause cancer) based on results from laboratory tests. NDMA
is a known environmental contaminant and found in water and foods, including meats, dairy
products, and vegetables.
The US Food and Drug Administration (FDA) has found levels of NDMA in some ranitidine
products similar to the levels you would expect to be exposed to if you ate common foods like
grilled or smoked meats. The ranitidine that will be used in this study has been tested twice
(months apart) and shown to have stable NDMA levels well below the acceptable daily limit. Of
note, the risk of NDMA with ranitidine is only relevant with prolonged chronic administration
as at the acceptable limit, there is approximately a 1 in 100,000 chance of cancer after 70
years of exposure to that level.
FDA has also conducted tests that simulate the potential formation of NDMA from ranitidine
after it has been exposed to acid in the stomach with a normal diet. Results of these tests
indicate that NDMA is not formed in typical stomach conditions. Similarly, if ranitidine is
exposed to a simulated small intestinal fluid, NDMA is not formed. Other laboratory
experiments suggest a combination of nitrites, such as found in processed meats, and an
acidic environment may increase NDMA formation, however the levels of nitrites tested were
very high. Separately, a previous study in 10 healthy volunteers showed that volunteers who
received ranitidine had an increase in urinary NDMA excreted over 24 h. The level of increase
was greater than would be expected from laboratory testing.
This clinical study is being performed to determine if and how much NDMA is produced from
ranitidine in the human body and whether nitrite-containing foods may increase formation of
NDMA. The study will use a prescription dose of ranitidine (300 mg) to test whether there is
increased urinary NDMA excretion levels over 24-hours after ranitidine administration in
comparison to placebo when participants are administered low nitrite/NDMA meals and when
subjects are administered high nitrite/NDMA meals. On 4 different days, each participant will
receive ranitidine or placebo with high nitrite/NDMA meals and ranitidine or placebo with low
nitrite/NDMA meals.
Description:
The U.S. Food and Drug Administration (FDA) has learned that some ranitidine medicines,
including some products commonly known as the brand-name drug Zantac, contain a nitrosamine
impurity called N-nitrosodimethylamine (NDMA) at low levels. NDMA is classified as a probable
human carcinogen (a substance that could cause cancer) based on results from laboratory
tests. NDMA is a known environmental contaminant and found in water and foods, including
meats, dairy products, and vegetables.
The FDA has been investigating NDMA and other nitrosamine impurities in blood pressure and
heart failure medicines called Angiotensin II Receptor Blockers (ARBs) since 2018. In the
case of ARBs, the FDA has recommended numerous recalls as it discovered unacceptable levels
of nitrosamines.
FDA has found levels of NDMA in ranitidine active pharmaceutical ingredient and finished
drugs that are similar to the levels you would expect to be exposed to if you ate common
foods like grilled or smoked meats. FDA has requested removal of all ranitidine products from
the market because some ranitidine products have NDMA levels above the acceptable limits (96
nanograms per day or 0.32 parts per million for 300 mg per day of ranitidine) and that levels
of NDMA in ranitidine may increase to unacceptable levels over time. However, FDA has not
withdrawn approvals of ranitidine new drug applications and abbreviated new drug applications
and if a company can show, through scientific data, that their ranitidine product is stable
and the NDMA levels do not increase over time to unsafe levels, FDA may consider allowing
that ranitidine product back on the U.S. market. The ranitidine that will be used in this
study has been tested twice (months apart) and shown to have stable NDMA levels well below
the acceptable daily limit. Of note, the risk of NDMA with ranitidine is only relevant with
prolonged chronic administration as at the acceptable limit, there is approximately a 1 in
100,000 chance of cancer after 70 years of exposure to that level.
FDA has also conducted tests that simulate the potential formation of NDMA from ranitidine
after it has been exposed to acid in the stomach with a normal diet. Results of these tests
indicate that NDMA is not formed in typical stomach conditions. Similarly, if ranitidine is
exposed to a simulated small intestinal fluid, NDMA is not formed. Other in vitro experiments
suggest a combination of nitrites, such as found in processed meats, and an acidic
environment potentiate formation of NDMA. For that reason, prior to requesting removal of
ranitidine products from the market, the FDA had advised consumers who wished to continue
taking these medications to consider limiting consumption of nitrite-containing foods.
Separately, a previous study in 10 healthy volunteers showed that single dose administration
of ranitidine 150 mg was associated with ~400-fold increase in urinary NDMA excreted over 24
h. This level of increase is substantially greater than would be expected from laboratory
testing. Further evaluation is necessary to determine if and how much NDMA is produced from
ranitidine in the human body and whether nitrite-containing foods may potentiate formation of
NDMA in vivo.
Ranitidine
Ranitidine is an over-the-counter (OTC) and prescription drug. Ranitidine is an histamine-2
(H2) blocker, which decreases the amount of acid secreted by the stomach. Over-the-counter
ranitidine is approved to prevent and relieve heartburn associated with acid ingestion and
sour stomach and the approved dosage regiment is up to 150 mg twice a day. Prescription
ranitidine is approved for multiple indications, including treatment and prevention of ulcers
of the stomach and intestines and treatment of gastroesophageal reflux disease and the
approved dosage regimen is up to 150 mg twice a day or 300 mg once a day.
Study Primary Objective
1. To evaluate 24-hour urinary excretion of NDMA after oral administration of ranitidine
compared to placebo
Study Exploratory Objectives
1. To evaluate plasma ranitidine, NDMA, and dimethylamine (DMA) after oral administration
of ranitidine compared to placebo
2. To evaluate urinary excretion amounts over 24-hours of ranitidine and DMA after oral
administration of ranitidine compared to placebo
3. To evaluate 24-hour urinary excretion and plasma concentration of NDMA and DMA with
administration of high nitrite/NDMA meals compared to low nitrite/NDMA meals
Study Design
This is a randomized, placebo-controlled, single-dose, 4-period crossover study with 18
healthy subjects. Subjects check-in on Day -2 and receive the following 4 treatments starting
on Day 1, with one washout day between treatment days. The treatments consist of oral
administration of either a single dose of ranitidine (300 mg) or placebo administered at time
0 hr. All subjects will be provided low nitrite/NDMA meals for the first two periods of the
study and high nitrite/NDMA meals for the last two periods of the study. This ordering of
meals will allow purchasing a single lot of perishable items for different meals and to
simplify meal preparation and serving at the study site. The four treatments are:
A. Ranitidine + low nitrite/NDMA meal;
B. Placebo + low nitrite/NDMA meal;
C. Ranitidine + high nitrite/NDMA meal;
D. Placebo + high nitrite/NDMA meal.
Subjects will report to the study site for screening from Days -28 to -3 and then will return
to the site on Day -2 for baseline assessments. Subjects will receive three standardized
meals and an evening snack per day starting on Day -1. Subjects will be served meals from a
pre-specified menu for check-in and for all washout and treatment days. Subjects will be
instructed to finish all their meals within 25 minutes with no leftovers. Subjects will only
consume foods served to them at planned meal and snack times.
Two different full day menus of low nitrite/NDMA and high nitrite/NDMA meals have been
developed. Additional details regarding the meals will be specified in the Meal Preparation
Plan. Meals will be identical for treatments A and B (low nitrite/NDMA meal) of the study and
a separate set of identical low nitrite/NDMA meals will be served on the washout days prior
to treatment. Likewise, meals will be identical for treatments C and D (high nitrite/NDMA
meal) and a separate set of identical high nitrite/NDMA meals will be served on the washout
days prior to treatment. The last meal on Day -1, Day 2, Day 4, and Day 6 should be
administered at approximately 18:00 to permit at least 12-hour fasting prior to dosing.
Outside of meal times, subjects will be provided with distilled water to drink throughout the
study.
On study treatment days, the first meal will be provided at the time of dosing. Subjects will
be instructed to swallow the medication with approximately 250 mL of room temperature
distilled water and begin eating one minute after dosing. Subjects are required to eat each
meal in its entirety during the study. If the meal is not finished, the reason should be
recorded, along with what was not eaten, and a picture of the remaining food should be taken.
Prior to and following study drug or placebo administration on Day 1, subjects will undergo
assessments as described in the Schedule of Events. There will be one day of washout between
periods. Participants will be confined in the study clinic from Day -2 until the morning of
Day 8.
During the screening visit, the inclusion and exclusion criteria will be reviewed to ensure
the subject is eligible for the study. Subjects will be shown the low and high nitrite/NDMA
menus and informed that each meal in the menu must be finished in its entirety. The subject
must agree to consume all planned meals in order to be eligible to participate. The informed
consent form will be reviewed with the subject by a member of the study team and the subject
will be encouraged to ask questions to ensure he or she has a good understanding of the
study. If the subject is eligible and agrees to participate, the subject will be asked to
sign the informed consent form before any study specific procedure is performed, including
randomization. Results of all screening tests will be evaluated by the study
clinician/investigator against the inclusion/exclusion criteria to confirm subject
eligibility. For subjects that are eligible, a molecular diagnostic test for severe acute
respiratory syndrome coronavirus 2 (SARS-CoV-2) will be performed just before or at check-in.
During the study, urine and blood samples for pharmacokinetic assessments will occur before
or after drug or placebo administration at the following timepoints:
- Urine samples will be collected using separate collection containers over 24 h.
Collection times will occur at 0 (pre-dose), 3, 6, 9, 12, 15, and 24 h. Subjects will be
instructed to void their bladder at each collection time and total weight of the sample
will be recorded. If a subject must void their bladder at an unscheduled time, the
unscheduled voids will be collected, and total weight of the unscheduled voiding will be
recorded. The unscheduled voiding sample will be treated, analytically analyzed, and
reported as part of scheduled sample collection for determining cumulative amounts of
NDMA, ranitidine, and DMA excreted over 24 h.
- Plasma samples will be collected at 0 (pre-dose), 0.5, 1, 1.5, 2, 3, 4, 5, 6, 9, 11, 14,
and 24 h post-dose.
Subjects will be discharged from the study after completion of all study procedures. If a
subject discontinues from the study prematurely, all procedures scheduled for the end of the
study will be performed. Meals (timing and components), activity levels, and general
conditions in the study clinic will be standardized to the extent possible on the treatment
days.