Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Class |
|---|---|
| Hospital das ClÃnicas de Ribeirão Preto | OTHER |
Not provided
Not provided
Not provided
Not provided
Not provided
This study aims to investigate the influence of the c.421C>A genetic polymorphism of the ABCG2 / BCRP transporter in the concentration ratio of nifedipine in maternal milk:plasma in hypertensive breastfeeding women attended at the Gynecology and Obstetrics Service of the Medical School of Ribeirão Preto, of the University of São Paulo. Thus, plasma and breast milk samples are being collected from patients in chronic use of the drug (n=30) within 15 to 30 days postnatal.
The breast cancer resistance protein (ABCG2/BCRP) human transporter, encoded by the ABCG2 gene, is highly expressed on the human lactating breast. Nifedipine, a known substrate of ABCG2, is used for the treatment of hypertension in pregnancy and during breastfeeding. ABCG2 plays an important role on secreting drugs and xenobiotics into milk. The aim of the present study was to evaluate the effect of ABCG2 c.421C>A on nifedipine breast milk/plasma concentration ratio in hypertensive breastfeeding women. Nineteen hypertensive breastfeeding women treated with 20 mg slow-release nifedipine every 12 hours were investigated. Blood and breast milk samples were collected simultaneously 15-30 days after delivery and at least 15 days after drug treatment, in order to reach drug steady state. All patients were genotyped for ABCG2 c.421C>A using real time-PCR. Nifedipine concentration was determined in plasma and breast milk by high-performance liquid chromatography using UV detection. The comprehension of the variability in the transport of nifedipine to breast milk in hypertensive breastfeeding women will contribute to the evaluation of drug exposure in breast-fed infants to nifedipine and other ABCG2 substrates.
Not provided
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Wild homozygous for ABCG2 c.421C>A | Active Comparator | Chronic hypertensive breastfeeding women (18-45 years old) genotyped as wild homozygous for ABCG2 c.421C>A. |
|
| Variant genotypes for ABCG2 c.421C>A | Experimental | Chronic hypertensive breastfeeding women (18-45 years old) genotyped as heterozygous or mutant homozygous for ABCG2 c.421C>A. |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Blood and breast milk sampling | Procedure | At least 15 days after starting treatment with 20 mg slow-release nifedipine every 12 hours. Blood and breast milk will be sampled before first dosing in the morning. |
| Measure | Description | Time Frame |
|---|---|---|
| Nifedipine concentration in plasma/milk ratio | The concentration ratio will be determined as (nifedipine concentration in plasma)/(nifedipine concentration in breast milk). | After reaching steady state (at least 15 days of treatment), samples will be collected before first nifedipine dosing in the morning. |
| Measure | Description | Time Frame |
|---|---|---|
| Nifedipine concentration in plasma | The concentration of nifedipine in plasma determined by HPLC. | After reaching steady state (at least 15 days of treatment), samples will be collected before first nifedipine dosing in the morning. |
| Nifedipine concentration in milk |
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| ID | Term |
|---|---|
| D001800 | Blood Specimen Collection |
| D009543 | Nifedipine |
| ID | Term |
|---|---|
| D013048 | Specimen Handling |
| D019411 | Clinical Laboratory Techniques |
| D019937 | Diagnostic Techniques and Procedures |
| D003933 | Diagnosis |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
|
| Nifedipine | Drug | Chronic hypertensive breastfeeding women will be treated with slow-release 20 mg nifedipine, twice a day. |
|
|
The concentration of nifedipine in breast milk determined by HPLC. |
| After reaching steady state (at least 15 days of treatment), samples will be collected before first nifedipine dosing in the morning. |
| D011677 | Punctures |
| D013514 | Surgical Procedures, Operative |
| D008919 | Investigative Techniques |
| D004095 | Dihydropyridines |
| D011725 | Pyridines |
| D006573 | Heterocyclic Compounds, 1-Ring |
| D006571 | Heterocyclic Compounds |