A UPLC-MS/MS method for therapeutic drug monitoring of etonogestrel

The influence of lifestyle factors on serum etonogestrel concentrations among contraceptive implant users

OBJECTIVE

To evaluate how diet, exercise, and substance use influence serum etonogestrel concentrations among contraceptive implant users.

STUDY DESIGN

We conducted a cross-sectional analysis of healthy, reproductive-age etonogestrel implant users. We assessed participants' current diet, exercise, and substance (alcohol, tobacco, marijuana) use habits while simultaneously measuring serum etonogestrel concentrations. We used linear modeling to test for associations between survey responses and etonogestrel concentrations.

RESULTS

Among 115 participants, exercise habits and substance use had no significant associations with etonogestrel concentrations, while increased caloric intake demonstrated inconsistent associations.

CONCLUSION

The lifestyle factors of diet, exercise, and substance use do not influence steady-state pharmacokinetics among contraceptive implant users.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov, NCT03092037.

Pilot study of a novel, alternative subdermal scapular insertion site for the etonogestrel contraceptive implant

OBJECTIVES

To assess the pharmacokinetics and pharmacodynamics of the etonogestrel (ENG) contraceptive implant when inserted at an alternative scapular site.

STUDY DESIGN

We conducted a pilot study of healthy, reproductive-age females who underwent subdermal insertion of an ENG implant over the inferior edge of the nondominant scapula (scapular insertion). We measured serum ENG levels over 1 year at nine time points. Participants completed questionnaires on insertion site and bleeding side effects. We collected photographs and video recordings of insertion and removal techniques.

RESULTS

We enrolled five participants (as prespecified), their median age was 26.0 years (range: 19.6-30.3), and median body mass index was 25.0 kg/m2 (range: 22.0-28.0). All serum ENG concentrations remained >90 pg/mL and were within the range of published data for arm insertion of ENG implant at all time points. The mean serum ENG level was 511.7 pg/mL (±168.2) at 1 week and 136.6 pg/mL (±21.8) at 12 months. During the first week after insertion, four of five participants noted insertion site pain with a median pain score of 2 (range 1-3), but all noted resolution by week two. Participants reported variable bleeding patterns consistent with standard ENG implant placement. At the end of the study, all participants reported satisfaction with the implant and would recommend scapular insertion to a friend.

CONCLUSIONS

Scapular insertion of the ENG contraceptive implant has similar pharmacokinetics to arm insertion over 1 year of use. This novel, alternative site was well tolerated and demonstrated similar bleeding side effects to standard arm insertion.

IMPLICATIONS

Subdermal scapular insertion of the etonogestrel contraceptive implant demonstrated similar pharmacokinetics to arm insertion over 1 year of use. Our pilot data support scapular insertion as an alternative site for ENG contraceptive implants, which could be beneficial for certain patient populations.

An exploratory study on the possible association of serum etonogestrel concentrations with mood concerns and symptoms among contraceptive implant users

OBJECTIVE

To evaluate if inter-individual variability in serum etonogestrel (ENG) concentrations accounts for variability in mood-related side effects among ENG implant users.

STUDY DESIGN

Participants underwent a single-time blood draw for measurement of serum ENG concentrations using a liquid-chromatography mass-spectrometry assay, and completed a questionnaire at enrollment that retrospectively assessed mood-related side effects during the period of implant use. For a subset of participants, Patient Health Questionnaire-9 (PHQ-9) scores, obtained for other clinical purposes, were also compared. We used independent medians tests and linear regression to evaluate associations between mood symptoms and serum ENG concentrations as our primary outcome.

RESULTS

Among 900 enrolled participants, 34% (306/900) reported mood changes on the baseline questionnaire. Of these, 31 (3.4%) participants also had documented PHQ-9 scores. Serum ENG concentrations (median 126.9 pg/mL [range 39.4-695.1]) were not associated with reported mood changes on the questionnaire (p = 0.19) or on the PHQ-9 (β = 0.00, 95% CI -0.03, 0.03).

CONCLUSION

Pharmacokinetic variability does not explain the inter-individual variability in mood-related side effects among ENG implant users.

IMPLICATIONS

Mood-related side effects and altered mental health metrics are commonly reported by etonogestrel contraceptive implant users but demonstrate wide inter-individual variability. Individual differences in serum drug levels do not appear to account for this variability in mood-related side effects, and so future research should focus on novel personal factors.

Validation of 24-hour trough concentration as a proxy for intensive pharmacokinetic measurements for a combined oral contraceptive pill containing desogestrel

OBJECTIVES

To confirm that 24-hour steady-state trough measurements (C24) are high-quality proxies for gold standard pharmacokinetic measurements (area under the curve [AUC]) of a combined oral contraceptive pill (COCP).

STUDY DESIGN

We conducted a 12-sample, 24-hour pharmacokinetic study in healthy reproductive-age females taking a COCP containing 0.15-mg desogestrel (DSG) and 30-μg ethinyl estradiol (EE). As DSG is a pro-drug for etonogestrel (ENG), we calculated correlations between steady-state C24 and 24-hour AUC values for both ENG and EE.

RESULTS

Among 19 participants at steady state, C24 measurements were highly correlated with AUC for both ENG (r = 0.93; 95% CI 0.83-0.98) and EE (r = 0.87; 95% CI 0.68-0.95).

CONCLUSIONS

Steady-state 24-hour trough concentrations are high-quality proxies for gold standard pharmacokinetics of a DSG-containing COCP.

IMPLICATIONS

Use of single-time trough concentration measurements at steady state provides excellent surrogate results for gold standard AUC values for both DSG and EE among COCP users. These findings support that large studies exploring interindividual variability in COCP pharmacokinetics can avoid the time- and resource-intensive costs associated with measuring AUC.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov, NCT05002738.

The effect of rifampin on serum etonogestrel concentrations and biomarkers of ovulation among contraceptive implant users: A pharmacokinetic and pharmacodynamic study

OBJECTIVES

Rifampin, a strong CYP3A inducer, is the gold standard for evaluating CYP3A-mediated drug-drug interactions. We aimed to evaluate the pharmacokinetic and pharmacodynamic effects of a short course (2 weeks) of rifampin on serum etonogestrel (ENG) concentrations and serologic measures of ovarian activity (endogenous estradiol [E2] and progesterone [P4]) among ENG implant users.

STUDY DESIGN

We enrolled healthy females using ENG implants for 12 to 36 months. We measured baseline serum ENG concentrations using a validated liquid chromatography mass-spectrometry assay and baseline E2 and P4 concentrations using chemiluminescent immunoassays. After 2 weeks of rifampin 600 mg daily, we repeated ENG, E2, and P4 measurements. We compared pre- and post-rifampin serum measurements using paired Wilcoxon signed-rank tests.

RESULTS

Fifteen participants completed all study procedures. Participants' median age was 28.2 years (range 21.8-34.1), median body-mass index was 25.2 kg/m2 (range 18.9-37.3), and median duration of implant use was 22 months (range 12-32). All participants experienced significant decreases from baseline ENG concentrations (median 164.0 pg/mL [range 94.4-265.0]) to post-rifampin measurements (median 47.8 pg/mL [range 24.7-82.8]) (p < 0.001). Serum E2 concentrations also significantly increased with rifampin exposure (median 73 pg/mL vs 202 pg/mL, p = 0.003); increases in serum P4 concentrations were not statistically significant (p = 0.19). Three participants (20%) experienced increased luteal activity, with one presumptively ovulating post-rifampin (P4 = 15.8 ng/mL).

CONCLUSIONS

With only short exposure to a strong CYP3A inducer, ENG implant users experienced clinically significant decreases in serum ENG concentrations that led to changes in biomarkers indicative of waning suppression of ovulation.

IMPLICATIONS

Even a short, 2-week course of treatment with rifampin places etonogestrel contraceptive implant users at risk for decreased contraceptive efficacy. Clinicians should counsel patients using etonogestrel implants considering any duration of rifampin therapy on the need for backup nonhormonal contraception or the use of an intrauterine device to avoid unintended pregnancies.

Development and validation of a multiplexed assay for the measurement of long-acting hormonal contraceptives in plasma via liquid chromatography-tandem mass spectrometry

BACKGROUND

Exogenous progestins are an effective tool for hormonal contraception and family planning. Progestins may be delivered as oral pills, intramuscular or subcutaneous injections, vaginal rings, or intrauterine devices. Drug concentrations may vary based on the route and duration of delivery. Measurement of synthetic steroids in blood plasma can aid in determination of product adherence, evaluation of drug-drug interactions, and investigation of unintended pregnancies.

METHODS

Drug-free K2EDTA plasma was spiked with the synthetic steroids etonogestrel (ETO), levonorgestrel (LNG), medroxyprogesterone acetate (MPA), and norethisterone (NET). Plasma was combined with isotopically labeled internal standards, and drugs were extracted via liquid-liquid extraction. Samples were then subjected to liquid chromatographic-tandem mass spectrometric (LC-MS/MS) analysis. The method was validated in accordance with regulatory recommendations. The assay was evaluated in a cohort of remnant plasma samples in individuals using one of the aforementioned progestins.

RESULTS

The analytical measuring range for ETO, MPA, and NET was 20-10,000 pg/mL; the primary linearity for LNG was 20-20,000 pg/mL. The method showed acceptable precision and accuracy for all progestins. Stability was established for 72 h with room temperature storage and through 3 freeze-thaw cycles. All analytes were stable in whole blood incubated at room temperature for 25 h, and at 40°C and 100% humidity for 2 h. Ion suppression was observed for all analytes spiked in plasma; average ion suppression was 31.6%, 66.6%, 32.1% and 41.2% for ETO, LNG, MPA, and NET, respectively. However, internal standards showed comparable ion suppression, and relative matrix effects were minimal. ETO, LNG, MPA, and NET could also be quantified accurately in K3EDTA plasma and serum. Progestins were successfully measured in remnant samples from individuals using hormonal contraceptives.

CONCLUSIONS

A multiplexed LC-MS/MS assay for the quantification of ETO, LNG, MPA, and NET has been developed and validated. The assay met acceptable performance characteristics and may be used in downstream studies to evaluate progestin pharmacology.

Effect of Topiramate on Serum Etonogestrel Concentrations Among Contraceptive Implant Users

OBJECTIVE

To evaluate topiramate and etonogestrel pharmacokinetic interactions in contraceptive implant users.

METHODS

We conducted a prospective, noninferiority study with healthy women using etonogestrel implants continuously for 12-36 months. We measured baseline serum etonogestrel concentrations and then began a 6-week titrated topiramate regimen to standard migraine (100 mg/day) and epilepsy (400 mg/day) dosages. We repeated serum etonogestrel concentrations at 3 weeks (100 mg/day), 4 weeks (200 mg/day), and 6 weeks (400 mg/day) of topiramate therapy. We measured etonogestrel using a validated liquid chromatography-tandem, mass-spectrometry assay and tested for noninferiority (less than 30% decrease) in serum etonogestrel concentrations from baseline.

RESULTS

We enrolled 48 total participants; 32 completed 3 weeks, 31 completed 4 weeks, and 27 completed all follow-up visits. Participants' median age was 25.3 years (range 18.3-37.2), median body mass index (BMI) was 25.5 kg/m2 (range 18.7-42.2), and median duration of implant use was 24 months (range 12-36). Median etonogestrel concentrations were 142 pg/mL (range 76.2-771) at baseline, 126 pg/mL (range 72.4-585) at 3 weeks, 119 pg/mL (range 65.6-542) at 4 weeks, and 105 pg/mL (46.2-859) at 6 weeks. The 95% CIs for mean percent change in serum etonogestrel concentrations from baseline were [-37.3%+16.9%], [-45.4%+5.2%], and [-66.8%+24.8%] at 3 weeks, 4 weeks, and 6 weeks, respectively. Excluding one participant who had a serum etonogestrel concentration less than 90 pg/mL at baseline, 30.8% of participants (8/26, 95% CI 14.3-51.8%) had a serum etonogestrel concentration less than 90 pg/mL at 6 weeks.

CONCLUSION

Though only a mild enzyme-inducing antiepileptic drug, concomitant topiramate use led to inferior serum etonogestrel concentrations among implant users, with a significant proportion reaching etonogestrel concentrations below the threshold for ovulatory suppression when taking antiepileptic dosages of topiramate.

FUNDING SOURCE

This study was primarily funded through an Investigator-Initiated Study grant from Merck Sharp & Dohme Corp [MISP#57073]. This work was also supported by NIH/NCATS CTSA Grant Number UL1 TR001082 and NICHD K12 Women's Reproductive Health Research Scholar Program (grant number 5K12HD001271-18).

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT03335163.

Variability in repeat serum etonogestrel concentrations among contraceptive implant users during the steady-release pharmacokinetic period

OBJECTIVE

To assess the variability of repeated measurements of serum etonogestrel concentration among contraceptive implant users.

STUDY DESIGN

We measured 3 consecutive serum etonogestrel concentrations, drawn weekly, in women using etonogestrel implants for 12 to 36 months. We used a repeated measures test to evaluate differences.

RESULTS

Among 20 participants, repeat serum etonogestrel concentrations did not differ from initial measurements (Friedman's test, p = 0.95). Mean serum etonogestrel concentrations had similar 95% confidence intervals at each time point: (134.09, 201.46), (135.08, 237.46), and (132.66, 192.45).

CONCLUSION

We confirm that single-time measurements of serum etonogestrel concentration are acceptable pharmacokinetic outcomes for etonogestrel implant studies.

IMPLICATIONS

Pharmacokinetic studies of the etonogestrel contraceptive implant assume single-time measurements are stable steady-state estimates based on small studies using older analysis methods. Our repeated measures study using modern liquid-chromatography mass-spectrometry analysis methods provides updated support for single-time pharmacokinetic measurements among etonogestrel implant users.

An exploratory study on the association of lifestyle factors with serum etonogestrel concentrations among contraceptive implant users

PURPOSE

To explore how diet and exercise habits associate with serum etonogestrel concentrations among contraceptive implant users.

MATERIALS AND METHODS

We conducted a secondary analysis of healthy, reproductive-age women using etonogestrel implants. This study was registered on ClinicalTrials.gov, NCT03092037. We assessed diet and exercise habits with two validated surveys: Healthy Eating Vital Signs and the Stanford Brief Activity Survey. Participants previously had their serum etonogestrel concentrations measured using a validated liquid-chromatography mass-spectrometry assay. We then used linear modelling to test for associations between survey responses and serum etonogestrel concentrations.

RESULTS

Among 129 participants, diet and exercise habits had no significant associations with serum etonogestrel concentrations (p = 0.22-0.72), with inconsistent effects found for increased caloric intake and sedentary lifestyle.

CONCLUSION

This exploratory study found no significant effect of diet or exercise habits on steady-state pharmacokinetics among contraceptive implant users.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov: NCT03092037.

Pharmacokinetics, metabolism and serum concentrations of progestins used in contraception

Many different forms of hormonal contraception are used by millions of women worldwide. These contraceptives differ in the dose and type of synthetic progestogenic compound (progestin) used, as well as the route of administration and whether or not they contain estrogenic compounds. There is an increasing awareness that different forms of contraception and different progestins have different side-effect profiles, in particular their cardiovascular effects, effects on reproductive cancers and susceptibility to infectious diseases. There is a need to develop new methods to suit different needs and with minimal risks, especially in under-resourced areas. This requires a better understanding of the pharmacokinetics, metabolism, serum and tissue concentrations of progestins used in contraception as well as the biological activities of progestins and their metabolites via steroid receptors. Here we review the current knowledge on these topics and identify the research gaps. We show that there is a paucity of research on most of these topics for most progestins. We find that major impediments to clear conclusions on these topics include a lack of standardized methodologies, comparisons between non-parallel clinical studies and variability of data on serum concentrations between and within studies. The latter is most likely due, at least in part, to differences in intrinsic characteristics of participants. The review highlights the importance of insight on these topics in order to provide the best contraceptive options to women with minimal risks.

Comparison of plasma etonogestrel concentrations sampled from the contralateral-to-implant and ipsilateral-to-implant arms of contraceptive implant users

OBJECTIVE

To compare plasma etonogestrel concentrations sampled from the contralateral- versus ipsilateral-to-implant arm.

STUDY DESIGN

Sub-analysis of a cross-sectional study in Botswana in 33 participants who provided contralateral and ipsilateral blood samples.

RESULTS

Plasma etonogestrel concentrations in contralateral and ipsilateral specimens were highly correlated (correlation coefficient = 0.99; p < 0.0001). Bland-Altman analysis of agreement showed that etonogestrel levels were on average 5.9 pg/mL higher (2.1%) in ipsilateral compared to contralateral specimens (95% confidence interval: -4.1, 15.9 pg/mL).

CONCLUSIONS

We found no meaningful differences in plasma etonogestrel concentrations between samples taken from the contralateral- versus ipsilateral-to-implant arm.

IMPLICATIONS

Our data suggest that etonogestrel plasma concentrations are unlikely to be meaningfully different between samples drawn from the ipsilateral- versus the contralateral-to-implant arms in etonogestrel contraceptive implant users.

A pilot study on the effect of isotretinoin on serum etonogestrel concentrations in contraceptive implant users

OBJECTIVE

To explore the pharmacokinetic interaction between isotretinoin, a cytochrome P-450 (CYP) inducer and potent teratogen, and the etonogestrel contraceptive implant.

STUDY DESIGN

We enrolled healthy reproductive-age women initiating isotretinoin and using an etonogestrel implant. We compared serum etonogestrel concentrations at baseline and after four and nine weeks of isotretinoin co-administration using a validated assay.

RESULTS

Among eight implant users, all serum etonogestrel concentrations remained >90 pg/mL during isotretinoin co-administration with no significant changes from baseline (p = 0.25, Friedman's test).

CONCLUSION

In this exploratory study, we found that isotretinoin did not cause serum etonogestrel concentrations to fall below the threshold for ovulatory suppression (<90 pg/mL) among implant users.

IMPLICATIONS

Reproductive-age women treated with isotretinoin require reliable contraception to prevent pregnancies impacted by teratogenic-effects. This small study demonstrates that contraceptive implant users maintained serum etonogestrel concentrations above the threshold for consistent ovulatory suppression during isotretinoin co-administration. The contraceptive implant remains an appropriate option for patients considering isotretinoin therapy.

Relationship Between Etonogestrel Concentrations and Bleeding Patterns in Contraceptive Implant Users

OBJECTIVE

To estimate whether serum etonogestrel concentrations influence bleeding patterns and related side effects in contraceptive implant users.

METHODS

We conducted a prospective cross-sectional study with healthy, reproductive-aged women using etonogestrel implants for 12-36 months. Participants completed a brief questionnaire to assess their current bleeding pattern and any experience of abnormal bleeding with the implant. We then measured serum etonogestrel concentrations. We also reviewed the charts of participants to determine whether a prescription for oral contraceptive pills was ever given for treatment of implant-related bothersome bleeding. We performed multivariable logistic regression to test for associations between serum etonogestrel concentrations and both bleeding patterns and related side effects.

RESULTS

We enrolled 350 women, and 59.4% reported having experienced abnormal bleeding with the contraceptive implant. Only 14.9% of participants reported amenorrhea and 37.7% reported monthly periods. Among participants with reviewable medical records (n=253), roughly 20% had received a prescription for oral contraceptive pills during implant use. Increasing serum etonogestrel concentrations were significantly associated with increasing odds of reporting abnormal bleeding (adjusted odds ratio [aOR] 1.005, P=.015) and increasing odds of having received an oral contraceptive pill prescription (aOR 1.008, P=.002). For every 100 pg/mL increase in serum etonogestrel concentration, contraceptive implant users in this study had 1.6 times the odds of reporting abnormal bleeding and 2.3 times the odds of having received a prescription as treatment for bothersome bleeding.

CONCLUSION

We found both objective and subjective evidence that higher levels of progestin from the contraceptive implant were associated with bleeding side effects experienced by women in this study. Pharmacologic variation may influence the side effects women experience with a variety of hormonal contraceptive methods, in turn affecting patient satisfaction and discontinuation rates.

Influence of Genetic Variants on Steady-State Etonogestrel Concentrations Among Contraceptive Implant Users

OBJECTIVE

To identify genetic variants that influence steady-state etonogestrel concentrations among contraceptive implant users.

METHODS

We enrolled healthy, reproductive-age women in our pharmacogenomic study using etonogestrel implants for 12-36 months without concomitant use of hepatic enzyme inducers or inhibitors. We collected participant characteristics, measured serum etonogestrel concentrations, and genotyped each participant for 120 single nucleotide variants in 14 genes encoding proteins involved in steroid hormone (ie, estrogens, progestins) metabolism, regulation, or function. We performed generalized linear modeling to identify genetic variants associated with steady-state etonogestrel concentrations.

RESULTS

We enrolled 350 women, who had a median serum etonogestrel concentration of 137.4 pg/mL (range 55.8-695.1). Our final generalized linear model contained three genetic variants associated with serum etonogestrel concentrations: NR1I2(PXR) rs2461817 (β=13.36, P=.005), PGR rs537681 (β=-29.77, P=.007), and CYP3A7*1C (β=-35.06, P=.025). Variant allele frequencies were 69.4%, 84.9%, and 5.1%, respectively. Our linear model also contained two nongenetic factors associated with etonogestrel concentrations: body mass index (BMI) (β=-3.08, P=7.0×10) and duration of implant use (β=-1.60, P=5.8×10); R for the model =0.17.

CONCLUSION

Only BMI and duration of implant use remained significantly associated with steady-state etonogestrel concentrations. Of the three novel genetic associations found, one variant associated with increased etonogestrel metabolism (CYP3A7*1C) causes adult expression of fetal CYP3A7 proteins and can consequently alter steroid hormone metabolism. Women with this variant may potentially have increased metabolism of all steroid hormones, as 27.8% (5/18) of CYP3A7*1C carriers had serum etonogestrel concentrations that fell below the threshold for consistent ovulatory suppression (less than 90 pg/mL). More pharmacogenomic investigations are needed to advance our understanding of how genetic variation can influence the effectiveness and safety of hormonal contraception, and lay the groundwork for personalized medicine approaches in women's health.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT03092037.

Relationship between patient characteristics and serum etonogestrel concentrations in contraceptive implant users

OBJECTIVE

To determine whether serum etonogestrel concentrations in contraceptive implant users are associated with certain individual patient characteristics.

STUDY DESIGN

We enrolled reproductive-age women using etonogestrel contraceptive implants between 12-36 months duration and measured a single serum etonogestrel concentration. Participants also completed a questionnaire about demographics.

RESULTS

We enrolled 350 participants; median age was 22.5 years (range 18.0-39.1), median months of implant use was 26.0 (range 12.0-36.0), and median body mass index was 25.7 kg/m2 (range 18.5-52.0). Our study population was primarily white/Caucasian (46.6% [163/350]) and Hispanic/Latina ethnicity (51.4% [180/350]). The median serum etonogestrel concentration was 137.4 pg/ml and etonogestrel concentrations varied 12.4 fold in the population (range 55.8-695.1 pg/ml). Using forward stepwise linear regression, months of implant use (β=-1.74, p<.001) and body mass index (β=-3.10, p<.001) were both significantly associated with decreased serum etonogestrel concentration with Black/African American race as a positive effect modifier (β=18.24, p=.099); R-squared for the model=0.13.

CONCLUSIONS

Individuals demonstrated a wide variability in serum etonogestrel concentrations, which can potentially affect side-effect profiles and efficacy. Increasing body mass index and longer duration of implant use were associated with small decreases in serum etonogestrel concentrations, while self-reported Black/African American race was associated with a non-significant increase. Despite these findings, most of etonogestrel variability was unaccounted for, suggesting that other clinical, pharmacologic, and genetic factors contributing to variability in etonogestrel concentrations remain to be determined.

IMPLICATIONS

Although increases in body mass index are associated with lower etonogestrel levels in contraceptive implant users, the majority of women will maintain serum concentrations that consistently suppress ovulation. Furthermore, certain patient characteristics can only explain a small portion (13%) of the variability in serum etonogestrel levels among contraceptive implant users.

Simultaneous quantitation of multiple contraceptive hormones in human serum by LC-MS/MS

OBJECTIVE

The objective was to develop a method to simultaneously quantify five commonly used hormonal contraceptives (HCs) and two endogenous sex steroids by liquid chromatography-tandem triple quadrupole mass spectrometry (LC-MS/MS) and apply this method to human serum samples.

STUDY DESIGN

We developed a method to simultaneously analyze ethinyl estradiol (EE2), etonogestrel (ENG), levonorgestrel (LNG), medroxyprogesterone acetate (MPA) and norethisterone (NET), along with estradiol (E2) and progesterone (P4), in human serum for a Shimadzu Nexera-LCMS-8050 LC-MS/MS platform. We analyzed serum collected from women self-reporting use of oral contraceptives, contraceptive implants or injectable contraceptives (n=14) and normally cycling women using no HC (n=15) as well as pooled samples from women administered various HCs (ENG, n=6; LNG, n=14; MPA, n=7; NET, n=5).

RESULTS

Limits of quantitation were 0.010ng/mL for E2, EE2 and P4; 0.020ng/mL for ENG, LNG and MPA; and 0.040ng/mL for NET. Precisions for all assays, as indicated by coefficient of variation, were less than or equal to 12.1%. Accuracies for all assays were in the range of 95%-108%. Endogenous hormone values obtained from analysis of human serum samples are in agreement with levels previously reported in the literature for normally cycling women as well as for women taking the appropriate HC.

CONCLUSIONS

We have developed a robust, accurate and sensitive method for simultaneously analyzing commonly used contraceptive steroids and endogenous sex steroids in human serum.

IMPLICATIONS

This analytical method can be used for quantitating contraceptive steroid levels in women for monitoring systemic exposure to determine drug interactions, nonadherence, misreporting and proper dosing.

Hormonal Contraception and HIV-1 Acquisition: Biological Mechanisms

Access to effective affordable contraception is critical for individual and public health. A wide range of hormonal contraceptives (HCs), which differ in composition, concentration of the progestin component, frequency of dosage, and method of administration, is currently available globally. However, the options are rather limited in settings with restricted economic resources that frequently overlap with areas of high HIV-1 prevalence. The predominant contraceptive used in sub-Saharan Africa is the progestin-only three-monthly injectable depot medroxyprogesterone acetate. Determination of whether HCs affect HIV-1 acquisition has been hampered by behavioral differences potentially confounding clinical observational data. Meta-analysis of these studies shows a significant association between depot medroxyprogesterone acetate use and increased risk of HIV-1 acquisition, raising important concerns. No association was found for combined oral contraceptives containing levonorgestrel, nor for the two-monthly injectable contraceptive norethisterone enanthate, although data for norethisterone enanthate are limited. Susceptibility to HIV-1 and other sexually transmitted infections may, however, be dependent on the type of progestin present in the formulation. Several underlying biological mechanisms that may mediate the effect of HCs on HIV-1 and other sexually transmitted infection acquisition have been identified in clinical, animal, and ex vivo studies. A substantial gap exists in the translation of basic research into clinical practice and public health policy. To bridge this gap, we review the current knowledge of underlying mechanisms and biological effects of commonly used progestins. The review sheds light on issues critical for an informed choice of progestins for the identification of safe, effective, acceptable, and affordable contraceptive methods.

Simultaneous determination of etonogestrel and ethinyl estradiol in human plasma by UPLC-MS/MS and its pharmacokinetic study

A selective, sensitive and rapid ultra-performance liquid chromatography tandem mass spectrometry method was developed and validated for the simultaneous determination of etonogestrel (ENG) and ethinyl estradiol (EE) in human plasma. The analytes and their deuterated internal standards, ENG-d7 and EE-d4, were extracted from plasma samples by solid-phase extraction on HyperSep™ Retain PEP cartridges. The chromatographic analysis was performed on an Acquity UPLC HSS Cyano column, 100 Å (50 × 2.1 mm, 1.8 μm), column using gradient mobile phase, acetonitrile and 2.0 mm ammonium trifluoroacetate at 0-1.7 min (65:35, v/v) and 1.8-2.7 min (95:5, v/v) with 0.250 mL/min flow rate. Analytes and IS protonated precursor → product ion transitions (ENG, m/z 325.2 → 257.2; EE, m/z 530.2 → 171.2; ENG-d7, m/z 332.2 → 263.2; EE-d4, m/z 534.2 → 171.2) were monitored on a Triple Quadrupole Mass spectrometer (TQMS), operating in multiple reaction monitoring and positive ionization mode. The calibration curves were established at 10.00-2500 pg/mL for ENG and 1.500-150.0 pg/mL for EE with a correlation coefficient (r² ) ≥0.9996 for both. The validated method was successfully applied to support a bioequivalence study of 0.15 mg ENG and EE 0.03 mg tablet formulation, administered in 24 healthy Indian females. Method reliability was assessed by reanalysis of 94 incurred study samples.

Electrochemical Sunset Yellow Biosensor Based on Photocured Polyacrylamide Membrane for Food Dye Monitoring

An enzyme-based electrochemical biosensor was investigated for the analysis of Sunset Yellow synthetic food dye. A glassy carbon electrode was coated with a poly(acrylamide-co-ethyl methacrylate) membrane to immobilize laccase using a single-step photopolymerization procedure. Poly(acrylamide-co-ethyl methacrylate) membrane was demonstrated to have acceptable water absorption and suitable for biosensor application. Sunset Yellow biosensor exhibited a linear response range from 0.08 to 10.00 µM with a detection limit of 0.02 µM. This biosensor was successfully used to determine Sunset Yellow in soft drinks with recoveries of 99.0-101.6%. The method was validated using high-performance liquid chromatography, indicating the biosensor can be as a promising alternative method for Sunset Yellow detection.

A UPLC-MS/MS method for the quantitation of Ulipristal acetate in human serum

The progesterone receptor modulator, Ulipristal acetate (UPA) has proven to be an effective emergency contraceptive. Conflicting data has been reported that suggests different efficacy of the drug in different populations, which may be explained by the systemic exposure to the drug. A UPLC-MS/MS method was developed and validated for the accurate and sensitive measurement of UPA in human serum to address this matter. UPA was extracted from human serum using liquid-liquid extraction with a combination of hexane and dichloromethane. An analytical platform comprising reverse-phase chromatographic separation followed by mass spectrometric detection by positive electrospray ionization in multiple reaction monitoring was used for quantitation of UPA within 7min. The method was linear from 0.1 to 250ng/mL. The matrix effect was minimal and intra- and inter-assay precision and accuracy were all within the acceptable limits. UPA was found to be stable at all processing and storage conditions. The method was used to investigate the pharmacokinetics of UPA in a clinical trial designed to explore the effect of obesity on its bioavailability.

High Variability of Hormonal Levels and No Clinically Relevant Interaction Between Ethinyl Estradiol, Desogestrel and Lopinavir/Ritonavir in a Small Sample of HIV-positive Adolescents

BACKGROUND

We report the pharmacokinetic interactions of combined oral contraceptive (COC) containing ethinyl estradiol (EE2)/desogestrel (DSG) with lopinavir/ritonavir (LPV/r) in 16 HIV-positive adolescents.

METHODS

We measured Ctrough of EE2 and etonogestrel (ENG), the active metabolite of DSG, in HIV-positives on LPV/r-based ART; Ctrough of LPV/r with and without COC; endogenous progesterone. EE2/ENG levels were compared with our own historical data of HIV-negative controls.

RESULTS

Ctrough of EE2 and ENG varied from 3 to 57 pg/mL and from 1051 to 5000 pg/mL, respectively. The geometric mean ratios (GMR) of Ctrough in HIV-positives on LPV/r with COC versus HIV-negative controls with COC only were 0.68 (95% CI: 0.42 to 1.08) or 32% decreased (P = 0.10) for EE2; and 1.08 (95% CI: 0.73 to 1.60) or 8% increased (P = 0.68) for ENG. Endogenous progesterone was <1.0 ng/mL in all participants, consistent with anovulation. Ctrough of LPV decreased statistically insignificantly with COC and remained above the desired therapeutic minimum of 1.0 mg/L in all.

CONCLUSIONS

The study found no clinically relevant interaction between EE2/DSG and LPV/r. This was supported by suppressed ovulation, assessed by low endogenous progesterone levels in all participants; and preserved antiretroviral activity, assessed by LPV/r levels above the desired therapeutic minimum in all participants. However, the high variability of hormonal levels warrants individual monitoring and further investigation. Condom use should always be encouraged for infection prevention.

Principle, Instrumentation, and Applications of UPLC: A Novel Technique of Liquid Chromatography

The key focus of the pharmaceutical or chemical industries is to reduce the cost involved in the development of new drugs and to improve the selectivity, sensitivity, and resolution for their detection. The purpose can now be solved by the separation method called UPLC which is the modified HPLC method comprising high pressure and small sized particles (less than 2 µm) used in the column, so the length of the column decreases leading to time saving and reduction in the consumption of solvent. The underlying principle of UPLC is based on van Deemter statement which describes the connection between linear velocity with plate height. UPLC contributes to the improvement of the three areas: speed, resolution, and sensitivity. This is a new advanced category of the HPLC which has the same basic principle and methodology with improved chromatographic performance. This review is an effort to compile the principle, instrumentation, and applications of UPLC.

Relationship between etonogestrel level and BMI in women using the contraceptive implant for more than 1 year

Progestin-only contraceptive methods, including the 3-year, single-rod etonogestrel (ENG) implant, may be preferred for obese women to avoid additional estrogen-related thrombosis risk; however, whether obese women receive an ENG sufficient dose to suppress ovulation is understudied. Our analysis expands on the limited information currently available by studying ENG levels related to body mass index (BMI) in a community sample of primarily Hispanic women. This cross-sectional, descriptive study of 52 long-term implant users found comparable ENG levels across a wide BMI range (p=.1). These results further support that ENG levels are independent of BMI through 3 years of implant use and are thus reassuring that ENG implants will be effective for women of all BMIs.