Reduced pelvic pain in women with endometriosis: efficacy of long-term dienogest treatment

Purpose To investigate the eYcacy and safety of dienogest as a long-term treatment in endometriosis, with follow-up after treatment discontinuation. The study included women with endometriosis, who had previously completed a 12-week, placebo-controlled study of dienogest, who participated in an open-label extension study for up to 53 weeks. Thereafter, a patient subgroup was evaluated in a 24-week follow-up after treatment discontinuation.

A multicenter study performed in Germany, Italy and Ukraine. Women with endometriosis were enrolled at completion of the placebo-controlled study (n = 168). All women received dienogest (2 mg once daily, orally) and changes in pelvic pain (on a visual analog scale), bleeding pattern, adverse events and laboratory parameters were evaluated during and after treatment.

The completion rate among women who entered the open-label extension study was 90.5% (n = 152). A sig- niWcant decrease in pelvic pain was shown during contin- ued dienogest treatment ( P < 0.001). The mean frequency and intensity of bleeding prog ressively decreased. Adverse events, rated generally mild or moderate, led to withdrawal in four patients (2.4%). No clinically relevant changes in laboratory parameters were observed. During treatment- free follow-up ( n = 34), the reduction in pelvic pain persisted, while bleeding frequency and intensity returned to normal patterns.

Long-term dienogest showed a favorable eYcacy and safety pro Wle, with progressive decreases in pain and bleeding irregularities during continued treatment; the decrease of pelvic pain persisted for at least 24 weeks after treatment cessation.

Dienogest · Endometriosis · Progestins · Pain · Safety

Endometriosis is a chronic, benign disease causing symp- toms of pelvic pain, dysmenorrhea and dyspareunia that often relapse after surgical therapy [ 1]. The aim of most Data from this study have been presented, in part, at the XIX FIGO World Congress of Gynecology & Obstetrics, Cape Town, South Africa, October 4–9, 2009, and the American Society for Reproductive Medicine 65th Annual Meeting, Atlanta, GA, USA, October 17–21, 2009. F. Petraglia (&) · S. Luisi · L. Lazzeri Department of Pediatrics, Obstetrics and Reproductive Medicine, University of Siena, Viale R. Bracci N. 16, 53100 Siena, Italy e-mail: [email protected] D. Hornung Department of Obstetrics and Gynecology, University of Schleswig-Holstein, Campus Lübeck, Lübeck, Germany C. Seitz Global Clinical Development Women’s Healthcare, Bayer HealthCare Pharmaceuticals, Berlin, Germany T. Faustmann Global Medical AVairs Women’s Healthcare, Bayer HealthCare Pharmaceuticals, Berlin, Germany C. Gerlinger Global Biostatistics, Bayer HealthCare Pharmaceuticals, Berlin, Germany T. Strowitzki Department of Gynecological Endocrinology and Reproductive Medicine, University of Heidelberg, Heidelberg, Germany 168 Arch Gynecol Obstet (2012) 285:167–173 123 medical therapies is to decrease the symptoms in order to improve quality of life, but many are associated with adverse eVects that restrict their long-term use. Gonadotropin-releasing hormone (GnRH) agonists are associated with symptoms of estrogen deprivation (e.g., hot Xushes, vaginal dryness, headache and decreased libido) and with bone demineralization that restricts use to 6 months in the absence of add-back therapy [2, 3]. In addition, the dura- tion of symptom relief following treatment cessation is typi- cally short, decreasing the cost-e Vectiveness of GnRH agonists as compared to other approaches [2]. Combined oral contraceptiv es, while widely used to manage symptoms of endometriosis, are not approved for this indication in most countries and their use is largely unsupported by solid clinical trial evidence [ 4]. One study has demonstrated that the use of a low-dose oral contraceptive pill is an e Vective treatment for dysmenorrhea associated with endometriosis [5]. The widespread use of danazol in endometriosis is lim- ited by adverse eVects typical of androgenic steroids, such as alterations in lipid pro Wle, weight gain, edema, acne, hirsutism and oily skin [ 6], although, in deeply inWltrating endometriosis, vaginal use may increase compliance [7]. Progestins are a recommended treatment for the pain associated with endometriosis, but a number of agents in this class are associated with androgenic eVects and weight gain at the doses that are required for e Ycacy [ 8]. Long- term use of depot medroxyprogesterone acetate prepara- tions impacts adversely on bone mineral density (BMD) [9]. Norethisterone acetate is a potent progestin derivative of 19-norethisterone and is valid for use in patients with endometriosis [ 8]; however, its main side e Vects include breast tenderness, weight gain, acne and hirsutism, in addition to breakthrough bleeding. Levonorgestrel (LNG) has also been used for treating women with symptomatic minimal-to-moderate endometriosis [ 10], leading to improvements in the severity and frequency of pain and men- strual symptoms. The LNG-intrauterine device (LNG-IUD) is an eVective treatment for rectovaginal endometriosis in women who have previously undergone conservative surgery without excision of deep lesions [11]. However, the LNG-IUD is not approved for the treatment of endometriosis. There remains, therefore, a need for an e Vective, safe and well-tolerated medical therapy that can be used in the long-term management of endometriosis. Dienogest is a selective progestin that combines the pharmacologic prop- erties of 19-norprogestins and progesterone derivatives, oVering a potent progestogenic e Vect at the endometrium. Clinical trials of 12–24 weeks’ duration have shown that dienogest (at a dose of 2 mg/day) provides e Vective pain relief equivalent to GnRH agonists, a reduction of endome- triotic lesions and a favorable safety and tolerability proWle in endometriosis [12–14]. A recent Japanese study investigated the e Y cacy of 52 weeks of dienogest administration for the treatment of endometriosis [ 15] and reported a marked or moderate improvement in symptoms in 90.6% of patients, with low rates of adverse event-related discontinuations and little impact on BMD. In a recent, double-blind, placebo-controlled European study of 198 women with endometriosis, dienogest for 12 weeks was signiWcantly more eVective than placebo in reducing endometriosis-associ ated pelvic pain (EAPP), with low rates of treatment -related adverse events [ 16]. With the aim to investigate the long-term safety and eYcacy of continuous dienogest treatment of endometriosis in this European network, a 1-year, open-label extension study to this placebo-controlled study was performed. In addition, at completion of the extension study, a subgroup of women was followed for 24 weeks without dienogest treatment.

Women with laparoscopically con Wrmed endometriosis who participated in a 12-week, multicenter, randomized, double-blind, placebo-controlled study of dienogest treat- ment at 2 mg once daily [16] were oVered and accepted par- ticipation in an open-label, single-arm extension study of dienogest treatment ( n = 168). The extension study was conducted at 28 centers in Germany ( n =1 7 ) , I t a l y (n =5 ) and Ukraine ( n = 6) between July 2004 and November 2007. The duration of treatment was initially planned to be 36 weeks, but was extended to 52 weeks during the course of the study. Twenty-six patients completed the study before this prolongation was introduced to the protocol. For the Wnal visit, a deviation of +1 week was allowed, result- ing in a maximum treatment duration of 12 weeks (in the placebo-controlled study) plus 53 weeks in the current study (total 65 weeks). An additional 24 weeks, treatment- free follow-up was conducted in a patient subgroup (n = 34) at six study centers on completion of the extension study. Therefore, an overall total of 90 weeks of study was conducted. The study protocol was approved by local independent ethics committees and all participants provided written, informed consent before study enrolment. The study was conducted in accordance with the amended version of the Declaration of Helsinki and complied with Good Clinical Practice guidelines. Inclusion and exclusion criteria for participation in the pla- cebo-controlled study are described in detail elsewhere [16]. In brief, the inclusion criteria for women aged 18–45 years included histologically proven endometriosis (stages 1–4) at laparoscopy ·12 months before study entry [ 17] and an Arch Gynecol Obstet (2012) 285:167–173 169 123 EAPP score of at least 30 mm on a 100-mm visual analog scale (VAS) at screening and baseline visits [ 16]. All women, who completed thei r allocated treatment with either dienogest or placebo in the placebo-controlled study, without major protocol violations, were eligible for inclu- sion in the extension study. All patients at speci Wc study centers who successfully completed the extension study were subsequently eligible for inclusion in the follow-up study. Dienogest was administered at a dose of 2 mg once daily, orally, for up to 53 weeks to all women during the extension study. The Wrst dienogest tablet during the exten- sion study was taken on the day after medication ended in the placebo-controlled study. Women completed a daily diary card throughout the extension study to monitor treat- ment compliance. Investigator s recorded the use of any concomitant medications. The main study variables were (1) EAPP, which was assessed by VAS score every 4 weeks to summarize the previous 4-week period (where 0 mm represents absence of pain and 100 mm indicates unbearable pain); (2) uterine bleeding pattern, which was assessed over 90-day periods according to the method of Gerlinger et al. [ 18]. Women documented the presence and intensity of bleeding on daily diary cards, from which the frequency and duration of bleeding events were calculated. Patient visits were planned at baseline and at weeks 2, 13, 25, 36 and 52 of the extension study, as well as at weeks 12 and 24 during the treatment-free follow-up. Adverse events were documented at all study visits and coded according to the Medical Dictionary for Regulatory Activities Primary System Organ Class. Adverse events were rated treatment-related at the discretion of the investigator. Laboratory assessments included hematology, blood chemis- try, liver enzyme, lipid and estradiol concentration mea- surements (Laboratorium für Klinische Forschung, Kiel, Germany) and dipstick urinalysis (“Combur-9”; Roche, Germany). Gynecologic examination (including cervical cytological smears), breast examination, vital sign assess- ments (blood pressure and heart rate) and body weight mea- surements were performed at prede Wned study visits. Abnormal Wndings at gynecologic and breast examination were reported as adverse events. Urine pregnancy testing was performed at home every 4 weeks and at study visits. Quality of life assessments by the Short Form 36 Health Survey Questionnaire (SF-36 ®) were performed at the base- line and the end of the follow-up study to measure changes in mental and physical components. Statistical analyses Analyses are based on the full analysis set (FAS), which included all women who took at least one dose of study medication and provided at least one observation after dos- ing. Subgroup analyses are reported for women treated with dienogest or placebo during the previous placebo- controlled study (“prior-dienogest” and “prior-placebo” groups, respectively). The eYcacy and safety analyses in the extension and follow-up studies are presented primarily as descriptive sta- tistics. The null hypothesis of whether the change in EAPP from randomization in the placebo-controlled study to the end of the extension study was equal to 0 was exploratively tested using the one-sample t test. The sample size of the extension study was determined by the number of women who were eligible and willing to participate at completion of the placebo-controlled study. According to the guidelines from the International Confer- ence on Harmonization, the extent of population exposure to assess clinical safety requires at least 100 patients stud- ied over 1 year. Assuming a dropout rate of 25%, the exten- sion study, therefore, required inclusion of a minimum of 133 women.

Among women who completed the placebo-controlled study (n = 188), 168 entered the extension study and were included in the FAS (Fig. 1). A total of 152 women (90.5%) completed the planned duration of the extension study (n = 17, 36 weeks; n = 135, 52 weeks). No predominant reason for withdrawal was identi Wed among women who discontinued. Treatment compliance, measured by daily diary cards during the extension study, was 98.3%. A sub- group of 34 women at six study centers began the 24 weeks, treatment-free follow-up, with completion by 31 (91.2%) (Fig. 1). Pelvic pain The mean VAS score at baseline of the extension study was 34.08 mm (standard deviation [SD] §21.60 mm) in the total population, resulting from mean scores of 27.89 (§20.24) mm in the dienogest-treated and 40.73 (§21.14) mm in the pla- cebo-treated subgroup. The mean VAS score progressively and signiWcantly decreased to 11.52 (§11.26) mm at the end of the extension study in the total population (9.72§ 7.44 mm in the prior-dienogest group and 13.49 § 14.14 mm in the prior-placebo group) (Fig.2). The mean VAS score was statis- tically signiWcantly reduced by 43.2 (§21.7) mm over the total treatment period of 65 weeks (i.e., the placebo-controlled plus extension study; P < 0.001). During the treatment-free follow-up, the mean VAS score increased slightly from the end of the extension study to 16.29 (§14.08) mm at week 12 and 14.56 (§9.55) mm at week 24. 170 Arch Gynecol Obstet (2012) 285:167–173 123 Uterine bleeding pattern Continued dienogest treatment during the extension study was associated with a progre ssive reduction in the number of bleeding/spotting days, number of bleeding/spotting episodes and duration of bleeding/spotting episodes between 90-day reference periods. Subgroup analysis during the extension study showed that both the prior-dienogest and the prior-placebo sub- groups of the placebo-controlled study experienced decreases in the number of bleeding/spotting days, number of spotting episodes and duration of bleeding/spotting epi- sodes. These decreases were greater in the prior-placebo than in the prior-dienogest subgroup. When comparing the frequency of maximal intensity of bleeding between 90-day reference periods 1 and 4, a sub- stantial increase in the “no bleeding” category, i.e., women who never bled during the entire reference period (from 5.5 to 23.5% of women) and a decrease in the “heavy bleeding” category (from 9.8 to 2.2%) was shown (Fig. 3). During treatment-free follow-up, bl eeding returned to normal cyclic patterns and intensity within 4–6 weeks. No patients reported amenorrhea or spotting during the Wnal 90-day ref- erence period of treatment-free follow-up. Safety variables Laboratory parameters (Table 1), vital signs and body weight remained stable or underwent minimal changes dur- ing the extension study. In patients whose body weight was assessed at both baseline and after 52 weeks of treatment (n = 124), a mean change of 0.58 (§2.09) kg was recorded. Laboratory parameters continued to show no or minimal changes during treatment-free follow-up, while vital sign and body weight assessments provided stable results. Fig. 1 Patient disposition dur- ing the extension study and the treatment-free follow-up period Fig. 2 Mean ( §SEM) VAS scores for EAPP during the extension study (FAS) in the total, prior-dienogest and prior-placebo groups. Mean VAS score was statistically signi Wcantly reduced by 43.2 (§21.7) mm over the total treatment period of 65 weeks (i.e., placebo- controlled plus extension study; P <0 . 0 0 1 ) . EAPP endometriosis- associated pain, FAS full analysis set, SEM standard error of the mean, VAS visual analog scale Arch Gynecol Obstet (2012) 285:167–173 171 123 Adverse events considered potentially drug related by the investigators developed in 27/168 women (16.1%) during the extension study, including breast discomfort (n = 7; 4.2%), nausea ( n = 5; 3.0%) and irritability ( n =4 ; 2.4%). The maximal intensity of treatment-related adverse events was rated mild or moderate in the majority (92.5%) of cases. Three women (1.8%) experienced one serious adverse event each of cholelithiasis, chronic sinusitis and depression; of these, only the case of depression, which developed after approximately 4 months of study drug treatment, was considered to be possibly treatment related. Four women (2.4%) experienced four adverse events (i.e., weight increase, migraine, depression and breast pain) that led to premature study discontinuation (Fig. 1). Two women (1.2%) discontinued the study due to bleeding- related events (amenorrhea and polymenorrhea), which were not recorded as adve rse events. Abnormal cervical smear Wndings were recorded in two women, which were considered unlikely to be treatment related. During treatment-free follow-up, 7/34 women (20.6%) developed de novo adverse events, including headache in two women (5.9%). One woman developed an ovarian cyst at the end of the follow-up period that was considered to be unrelated to previous study drug intake. Another woman had a successful, planned pregnancy, with conception esti- mated at approximately 6 mon ths after ceasing treatment. Quality of life assessment by the SF-36 ® indicated minimal change in mental or physical sum scores during the follow- up period. Fig. 3 Frequencies of maximal intensity of bleeding in 90-day refer- ence periods 1 and 4 during dienogest treatment in the extension study (FAS) FAS full analysis set Table 1 Selected laboratory parameters during dienogest treatment in the extension study Values are number of women or mean § SD HbA1C hemoglobin A1C, HDL high-density lipoprotein, LDL low-density lipoprotein a Includes patients with a predeWned treatment duration of 36 or 52 weeks, respectively Parameter Baseline of extension study Absolute change from baseline to end of treatmenta Normal range n Mean § SD n Mean § SD Hematology Erythrocytes (1012/L) 167 4.46 § 0.34 155 –0.01 § 0.30 3.6–5.0 Leukocytes (109/L) 166 5.94 § 1.82 154 0.21 § 2.15 4.0–10.0 Platelets (g/L) 167 248.4 § 66.40 155 –1.3 § 60.60 150–450 HbA1c (%) 168 5.16 § 0.31 157 –0.13 § 0.29 4.3–6.1 Serum lipid concentrations Total cholesterol (mmol/L) 168 4.86 § 0.97 161 –0.05 § 0.94 4.14–6.73 HDL cholesterol (mmol/L) 168 1.53 § 0.33 161 –0.04 § 0.36 1.09–2.28 LDL cholesterol (mmol/L) 168 2.91 § 0.75 161 0.10 § 0.71 1.97–5.65 Triglycerides (mmol/L) 168 1.05 § 0.61 161 0.03 § 0.57 0.80–1.94 Liver enzymes Alkaline phosphatase (U/L) 168 54.2 § 17.61 161 3.6 § 17.36 35–104 Gamma glutamyl transferase (U/L) 168 18.1 § 16.40 161 2.3 § 23.66 5–39 Alanine aminotransferase (U/L) 168 15.2 § 11.35 161 1.6 § 13.61 0–31 Cholinesterase (U/L) 168 7,463.4 § 1,421.20 161 –116.9 § 1,473.26 3,650–11,250 Hormones Estradiol (nmol/L) 163 0.26 § 0.32 151 0.02 § 0.44 0.03–1.03 172 Arch Gynecol Obstet (2012) 285:167–173 123

The present study shows that dienogest treatment for up to 65 weeks is associated with reduced pelvic pain in women with endometriosis, and that this e Vect persists for at least 24 weeks after the end of treatment. Previous studies of dienogest treatment for periods of 12–24 weeks reported superior eYcacy relative to placebo [ 16] and equivalent eYcacy compared with leupro lide acetate and buserelin acetate [ 14, 19] in relieving the symptoms of endometri- osis. The present Wndings suggest that dienogest represents an eVective treatment over the long term. The observation that pain relief is also largely maintained during the 24 weeks after treatment cessation may indicate that dienogest—at least for a certain period—sustains a bene W- cial eVect that exceeds the period of symptomatic treat- ment. One plausible explanation for this e Vect is the reduction in endometriotic lesions observed during dieno- gest treatment [13], although additional explanations for the sustained reduction in pain are possible. Dienogest and other progestins have a number of putative mechanisms of action in endometriosis, including reduced growth, prolifer- ation and neoangiogenesis of lesions [ 20, 21] as well as an antiinXammatory eVect [22]. Assessment of uterine bleeding by a number of analyses showed that dienogest is associated with a desynchronized uterine bleeding in the short term, but with a progressive reduction in the frequency and intensity of bleeding during continued treatment. Irregul ar bleeding has also been reported in short-term studies of dienogest treatment [13, 16, 19]. The bleeding pattern associated with dienogest appeared to be generally acceptable, as only 2 of 168 women in the extension study discontinued treatment due to changes in their bleeding pattern. The incidence of menorrhagia was lower in this study than in the Japanese long-term study, which reported a 71.9% incidence of menorrhagia; in that study, 18 of 135 patients (13.3%) discontinued treatment for various reasons [15]. Irregular uterine bleeding is a known common adverse eVect of all long-term progestin treatments [ 8]. Informing women of the bleeding proWle of dienogest before they ini- tiate treatment will likely enhance their long-term adher- ence to therapy in light of the accompanying improvement in painful symptoms. The safety variables included in the extension study also indicated an acceptable pro Wle for dienogest. The lack of changes in laboratory parameters supports previous trials that investigated the metabolic eVects of dienogest [ 13, 14, 16, 23]. In addition, there were minimal changes in mean body weight, consistent with the previous dienogest experience [13, 14, 16]. This study contributes to the evidence base on medica- tions investigated for the long-term treatment of endometri- osis. The strengths of the current study include the assessment of clinically relevant outcomes, the long-term (1 year) treatment duration, and a treatment-free follow-up, which are pertinent for the management of patients with endometriosis. The data from the follow-up period may be especially relevant for patients who wish to become pregnant after a course of medical therapy. Potential weaknesses of the study are its open-label design and the recruitment of patients who had participated in an earlier placebo-controlled study, which included a proportion who responded favorably to prior dienogest therapy. The low and comparable discontinu- ation rates in both subgroups, during and at the end of the placebo-controlled study indicate that this theoretical concern did not introduce a major bias. In summary, this large-scale, long-term study showed that dienogest treatment induces a sustained reduction in EAPP associated with a favorable safety and tolerability proWle. The observation of prolonged pain relief even after the return of normal menses suggests a sustained e Vect on endometrial lesions. Bleeding irregularities demonstrated a tendency toward reduced frequency and intensity during continued treatment. Therefore, dienogest may represent an eVective long-term treatment option for women with endometriosis. Acknowledgments Editorial support was provided by PAREXEL. Funding for this study (A39700 and A43288) was provided by Bayer HealthCare Pharmaceuticals, Berlin, Germany. ConXict of interest F.P., S.L., L.L. and T.S. have no commercial interest, Wnancial interest and/or other relationship with manufacturers of pharmaceuticals, laboratory supplies and/or medical devices or with commercial providers of medically related services. D.H. has cooper- ation contracts with and has received a grant from Bayer HealthCare Pharmaceuticals. C.S., T.F. and C.G. are full-time employees of Bayer HealthCare Pharmaceuticals. Open Access This article is distributed under the terms of the Crea- tive Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.

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