Concentrations of tenofovir, lamivudine and efavirenz in mothers and children enrolled under the Option B-Plus approach in Malawi
Bibliographic record
Abstract
OBJECTIVES: To evaluate antiretroviral drug concentrations in mothers and infants enrolled under the Option B-Plus approach for the prevention of HIV mother-to-child transmission in Malawi and to assess the maternal virological response after 1 year of treatment. PATIENTS AND METHODS: Forty-seven women and 25 children were studied. Mothers were administered during pregnancy a combination of tenofovir, lamivudine and efavirenz and continued it during breastfeeding (up to 2 years) and thereafter. Drug concentrations were evaluated in mothers (plasma and breast milk) at 1 and 12 months post-partum and in infants (plasma) at 6 and 12 months of age. Drug concentrations were determined using an LC-MS/MS validated methodology. RESULTS: In breast milk, tenofovir concentrations were very low (breast milk/maternal plasma ratio = 0.08), while lamivudine was concentrated (breast milk/plasma ratio = 3) and efavirenz levels were 80% of those found in plasma. In infants, median levels at 6 months were 24 ng/mL tenofovir, 2.5 ng/mL lamivudine and 86.4 ng/mL efavirenz. At month 12, median levels were below the limit of quantification for the three drugs. No correlation was found between drug concentrations and laboratory parameters or indices of growth. HIV-RNA >1000 copies/mL was seen at month 1 in 15% of the women and at month 12 in 8.5%. Resistance was found in half of the women with detectable viral load. CONCLUSIONS: Breastfeeding infants under Option B-Plus are exposed to low concentrations of antiretroviral drugs. With this strategy, mothers had a good virological response 1 year after delivery.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".