Efficacy, safety, and tolerability of a levonorgestrel/ethinyl estradiol transdermal delivery system: Phase 3 clinical trial results

OBJECTIVE

To assess the contraceptive efficacy, safety, and tolerability of a contraceptive transdermal delivery system, (TDS; TWIRLA^Ⓡ) containing levonorgestrel (LNG) and ethinyl estradiol (EE).

STUDY DESIGN

This single-arm, open-label, multicenter, 1-year (13 cycle), phase 3 study enrolled sexually active women ≥18 years old at risk for pregnancy irrespective of body mass index (BMI). Women used patches in 28-day cycles (3 consecutive administrations of 7-day patches followed by 7 days off-treatment/patch-free week). We assessed contraceptive efficacy by the Pearl Index (PI) in women 18 to 35 years, excluding cycles without intercourse or when other contraceptive methods were used.

RESULTS

The study enrolled 2032 demographically diverse women in the US, of which 35.3% had a BMI ≥30 kg/m². In the primary efficacy analysis, the PI (95% confidence interval) was 5.8 (4.5-7.2) pregnancies per 100 woman-years. PIs trended higher as BMI increased; the PI was 4.3 (2.9-5.8) in women with BMI <30 kg/m² and 8.6 (5.8-11.5) in women with BMI ≥30 kg/m². Hormone-related treatment-emergent adverse events included nausea (4.1%) and headache (3.6%); 11% of women discontinued due to adverse events. Four women (all with BMIs ≥30 kg/m²) reported thromboembolic events considered related to treatment.

CONCLUSIONS

The low-dose LNG/EE TDS was effective in preventing pregnancy in a population of women representative of US demographics. Efficacy was reduced in women with BMI ≥30 kg/m². The TDS safety and tolerability profile was consistent with other similar dose combined hormonal contraceptives. Results of this phase 3 study supported the US Food and Drug Administration approval of TWIRLA^Ⓡ for prevention of pregnancy in women with BMI <30 kg/m².

IMPLICATIONS

TDS (120 µg/day levonorgestrel and 30 µg/day ethinyl estradiol) is an effective, low-dose transdermal contraceptive patch with favorable tolerability profile approved for prevention of pregnancy in women with BMI <30 kg/m². TDS has reduced effectiveness in women with BMI ≥30 kg/m².

Current Management of Hyponatremia in Acute Heart Failure: A Report From the Hyponatremia Registry for Patients With Euvolemic and Hypervolemic Hyponatremia (HN Registry)

Background

Hyponatremia (HN) occurs commonly in patients with acute heart failure and confers a worse prognosis. Current HN treatment varies widely, with no consensus. This study recorded treatment practices currently used for patients hospitalized with acute heart failure and HN.

Methods and Results

Data were collected prospectively from 146 US sites on patients hospitalized with acute heart failure and HN (serum sodium concentration [Na⁺] ≤130 mEq/L) present at admission or developing in the hospital. Baseline variables, HN treatment, and laboratory values were recorded. Of 762 patients, median [Na⁺] was 126 mEq/L (interquartile range, 7) at baseline and increased to 130 mEq/L at discharge. Fluid restriction was the most commonly prescribed therapy (44%), followed by no specific HN treatment beyond therapy for congestion (23%), isotonic saline (5%), tolvaptan (4%), and hypertonic saline (2%). Median rate of change in [Na⁺] varied by treatment (0.5 [interquartile range, 1.0] to 2.3 [8.0] mEq/L/d) and median treatment duration ranged from 1 (interquartile range, 1) to 6 (5) days. Fluid restriction and no specific HN treatment resulted in similar changes in [Na⁺], and were least effective in correcting HN. Few patients (19%) had [Na⁺] ≥135 mEq/L at discharge.

Conclusions

The most commonly used treatment approaches for HN (fluid restriction and no specific treatment) in acute heart failure increased [Na⁺] minimally, and most patients remained hyponatremic at discharge.

Diagnosing and Treating the Syndrome of Inappropriate Antidiuretic Hormone Secretion

BACKGROUND

The syndrome of inappropriate antidiuretic hormone secretion is the most common cause of hyponatremia in clinical practice, but current management of hyponatremia and outcomes in patients with syndrome of inappropriate antidiuretic hormone secretion are not well understood. The objective of the Hyponatremia Registry was to assess the current state of management of hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion in diverse hospital settings, specifically which diagnostic and treatment modalities are currently used and how rapidly and reliably they result in an increase in serum sodium concentration ([Na(+)]). A secondary objective was to determine whether treatment choices and outcomes differ across the United States and the European Union.

METHODS

The Hyponatremia Registry recorded selected diagnostic measures and use, efficacy, and outcomes of therapy for euvolemic hyponatremia diagnosed clinically as syndrome of inappropriate antidiuretic hormone secretion in 1524 adult patients with [Na(+)] ≤130 mEq/L (1034 from 146 US sites and 490 from 79 EU sites). A subgroup of patients with more rigorously defined syndrome of inappropriate antidiuretic hormone secretion via measurement of relevant laboratory parameters was also analyzed.

RESULTS

The most common monotherapy treatments for hyponatremia in syndrome of inappropriate antidiuretic hormone secretion were fluid restriction (48%), isotonic (27%) or hypertonic (6%) saline, and tolvaptan (13%); 11% received no active agent. The mean rate of [Na(+)] change (mEq/L/d) was greater for all active therapies than no active treatment. Hypertonic saline and tolvaptan produced the greatest mean rate of [Na(+)] change (interquartile range, both 3.0 [6.0] mEq/L/d) compared with lower interquartile range rates of [Na(+)] change for isotonic saline (1.5 [3.0] mEq/L/d) and fluid restriction (1.0 [2.3] mEq/L/d). The general pattern of responses was similar in both the US and EU cohorts. At discharge, [Na(+)] was <135 mEq/L in 75% of patients and ≤130 mEq/L in 43% of patients. Overly rapid correction occurred in 10.2% of patients.

CONCLUSIONS

Current treatment of hyponatremia in syndrome of inappropriate antidiuretic hormone secretion often uses therapies with limited efficacy; the most commonly chosen monotherapy treatments, fluid restriction and isotonic saline, failed to increase the serum [Na(+)] by ≥5 mEq/L in 55% and 64% of monotherapy treatment episodes, respectively. Appropriate laboratory tests to diagnose syndrome of inappropriate antidiuretic hormone secretion were obtained in <50% of patients; success rates in correcting hyponatremia were significantly higher when such tests were obtained. Few outcome differences were found between the United States and the European Union. A notable exception was hospital length of stay; use of tolvaptan was associated with significantly shorter length of stay in the European Union but not in the United States. Despite the availability of effective therapies, most patients with syndrome of inappropriate antidiuretic hormone secretion were discharged from the hospital still hyponatremic.

Abstract P5-08-49: Incidence and prognostic importance of hyponatremia in a cohort of patients with breast cancer

Background: It has been suggested that hyponatremia (HN) may be a negative prognostic factor in patients with cancer but little research has been conducted specifically in breast cancer (BC). We measured the incidence of hyponatremia (hypervolemic and euvolemic) after BC diagnosis and its prognostic importance for progression free (PFS) and overall survival (OS).

Methods: This retrospective cohort analysis utilized data from the Henry Ford Health System electronic medical record, tumor registry, and administrative databases. Study data were collected electronically and via medical record abstraction. Adults diagnosed (2002-2010) with incident invasive BC were selected if they had a known disease stage at the time of tumor registration, were classified as an analytic case, had ≥ 1 administration of chemo/radiation therapy ≤ 6 months from diagnosis, met continuous enrollment thresholds, and did not experience hypovolemic HN post index. Only the first tumor registered from each patient was considered study-eligible. Hypervolemic or euvolemic HN incidence (serum sodium ≤ 135 mEq/L) was measured per 1000 person-years (PY) of observation and classified as mild (131–135 mEq/L), moderate (125–130 mEq/L) or severe (&lt;125 mEq/L) based on the lowest observed value. A Cox proportional hazards model was used to assess the prognostic value of HN as a time-varying covariate on PFS and OS while controlling for age, race, income, morphology code, diagnosis year, cancer stage at diagnosis, performance status at diagnosis, and hormone receptor status.

Results: 527 patients were eligible (mean [SD] age 56.4±11.3 years, 61% Caucasian). Mean (SD) follow-up was 3.7±2.8 years. Eighty-five percent of patients had infiltrating ductal carcinoma; 72% and 65% had estrogen or progesterone sensitive tumor, respectively; 35% were HER2 positive; and 15% had triple negative disease. Eighty-two percent of patients had early stage (I, II) disease at time of diagnosis. HN episodes (n=377) occurred in 204 patients (39%) at a rate of 193 per 1000 PY (95% CI, 174–213.5), with 89% of the total episodes (337/377) classified as mild, 10% (36/377) as moderate, and 1% (4/377) as severe. Additionally, 7% of all BC patients (37/527) had at least one episode of moderate/severe HN. Median time to first HN episode was 174.5 days and the median HN episode duration was 24.0 days. Five year OS in patients developing HN was 92%, compared to 97% in patients who never developed HN. Hazard ratio (95% CI, p-value) for OS in the HN group was 4.4 (1.5-12.7; p=0.006) after controlling for age, diagnosis year, race, income, morphology, cancer stage, performance status, and hormone receptor status. Fifty patients had progressive disease during follow-up with a mean (SD) time to progression of 763.4 (758.1) days. Hazard ratio (95% CI, p-value) for PFS in the HN group was 1.4 (0.8-2.7; p=0.262) after controlling for age, race, income, morphology, cancer stage, performance status, and hormone receptor status.

Conclusions: Incidence of hypervolemic or euvolemic HN is high (39%) after a BC diagnosis, and the occurrence is associated with significantly poorer OS. A significant impact on disease progression was not observed.

Citation Format: Castillo JJ, Glezerman IG, Boklage SH, Lamerato LE, Chiodo JA, Tidwell BA, Schulman KL. Incidence and prognostic importance of hyponatremia in a cohort of patients with breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-49.