A disproportionality analysis of adverse events caused by GnRHas from the FAERS and JADER databases

Background Gonadotrophin-releasing hormone analogs (GnRHas) play a significant role in addressing gynecological diseases, central precocious puberty, and cancer. However, ensuring the safety of GnRHas in real-world applications requires continuous vigilance. In light of this, we undertook a disproportionality analysis focused on adverse events (AEs) associated with GnRHas using data from both the FDA Adverse Event Reporting System (FAERS) and the Japanese Adverse Drug Event Report (JADER). We evaluated GnRHas-associated AEs and characterized the clinical priority of unlisted AEs caused by each GnRHa from the different databases. Methods In the disproportionality analysis, we applied two adjusted algorithms to identify signals related to GnRHas in the FAERS and JADER databases from 2004 to 2023. Additionally, we utilized the Statistical Analysis System (SAS, 9.4) to examine potential and high-aROR (adjusted reporting odds ratio) signals associated with GnRHas. We performed clinical priority assessment for suspicious PTs and an analysis of serious/non-serious outcomes. We also gathered information on the onset times of AEs linked with GnRHas from both databases. Results From January 2004 to September 2023, FAERS and JADER recorded a total of 50,360,413 and 1,440,200 AEs, respectively. Employing two algorithms, the suspicious preferred terms (PTs) related to leuprolide (Leu) were 562 potential PTs (44 unlisted in specifications), followed by goserelin (Gos) with 189 PTs (28 unlisted), triptorelin (Tri) with 172 PTs (28 unlisted), and Leu-JADER with 85 PTs (10 unlisted). At the same PT level, the differences in GnRHas between the two databases were observed, such as cardiac failure, diabetes mellitus, liver disorder, dementia, suicidal ideation, interstitial lung disease, urinary disorders, and hypertensive crisis. In an analysis of serious vs. non-serious outcomes, a total of 43 AEs of Leu were more likely to be reported as serious AEs with p < 0.05 (such as asthenia, urinary retention, diabetes mellitus, interstitial lung disease, gait disturbance, and so on), following by Tri (6 AEs), and Gos (4 AEs). Based on the clinical priority score, 41 PTs of Leu, 26 PTs of Tri, 24 PTs of Gos, and 8 PTs of Leu-JADER were graded as weak. There were 3 PTs of Leu, 2 PTs of Tri, 4 PTs of Gos, and 2 PTs of Leu-JADER that were graded as moderate. Notably, in the assessment of the relevant evidence, 2 PTs (loss of libido and urinary tract toxicity caused by Leu), 1 PT (electrolyte imbalance caused by Tri), and 2 PTs (anorexia and suicidal ideation caused by Gos) showed a strong level of evidence with “++.” The differences in the signal strength of the same PTs from two databases were also worth noting. Moreover, the median onset time for GnRHas (Leu, Tri, and Gos) was 23 days (0, 298), 22 days (0, 181), and 217 days (29, 706), respectively, as median (Q1, Q3). Conclusion An examination of two databases revealed suspicious AEs associated with GnRHas. Our study found potential new AE signals of GnRHas and supported continuous clinical monitoring, pharmacovigilance, regional differences, and further studies of GnRHas.


Introduction
Hormone-dependent cancers, such as breast and prostate cancers, constitute over 20% of all cancers globally and over 35% of cancers in women (Sung et al., 2021;Rižner and Romano, 2023).Imbalances at any level of the hypothalamic-pituitary-gonadal (HPG) axis may lead to various hormone-dependent diseases (HDDs), including precocious puberty, infertility, hormonedependent cancers, polycystic ovarian syndrome, endometriosis, and uterine fibroids (Newton et al., 2018).Gonadotropinreleasing hormone analogs (GnRHas), synthetic derivatives of the hormone gonadorelin, stimulate the pituitary gland within the brain, promoting the production of reproductive hormones, including luteinizing hormone (LH) and follicle-stimulating hormone (FSH) (Veth et al., 2023).
Hormone-dependent diseases also include noncancerous conditions such as precocious puberty, endometriosis, uterine fibroids, Cushing's syndrome, and polycystic ovarian syndrome (PCOS) (Zondervan et al., 2020;Rižner and Romano, 2023).Although these conditions are non-life-threatening, they significantly impact quality of life.Hormonal therapy refers to both androgen deprivation therapy for prostate cancer and endocrine therapy for breast cancer (Okwuosa et al., 2021).Approximately 10% of women of reproductive age are affected by endometriosis.Additionally, central precocious puberty (CPP) is a prevalent pediatric hormone-dependent disorder (HDD) that can result in the premature activation of the hypothalamic-pituitary-gonadal (HPG) axis.It is noteworthy that approximately 90% of girls with CPP experience idiopathic central precocious puberty (ICPP) (Zondervan et al., 2020;Hou et al., 2024).CPP could affect the physical and psychological health of children.Since the 1980s, GnRHas, acting as inhibitors binding to the GnRH receptor in the anterior pituitary, have been extensively employed for the treatment of CPP (Carel et al., 2009).Furthermore, the combination of GnRHas with chemotherapy in premenopausal patients with breast cancer has been shown to decrease the risk of premature ovarian insufficiency, which also contributes to the restoration of ovarian function (Zong et al., 2022).However, the prolonged administration of GnRHas, including leuprorelin, triptorelin, goserelin, buserelin, and histrelin, leads to the suppression of gonadal function.Consequently, this influence extends to hormone levels within the HPG axis, including testosterone, estrogen, and progesterone (Harris et al., 2022;Raja et al., 2022).GnRHas also could result in a reduction in ovarian hyperstimulation syndrome and bone mineral density, like menopausal symptoms, since they momentarily halt the synthesis of reproductive hormones (Fatemi and Garcia-Velasco, 2015;Veth et al., 2023).A study examining bone mineral density (BMD) in short children undergoing growth hormone (GH) and GnRHas treatment revealed that 2 years of GnRHas supplementation, alongside GH treatment, had no adverse effects on BMD or body composition (Lem et al., 2013).In addition to hormone-related symptoms such as hot flushes, osteopenia, and reproductive system disorders, what other adverse events (AEs) could potentially be induced by GnRHas?
Recently, two large real-world spontaneous adverse event reporting databases-the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) and the Japanese Adverse Drug Event Report (JADER) -have collected abundant AEs reports from different cohorts (one mainly from America and one mainly from the Japan) (Neishi et al., 2023).These two databases are reported to have different features, such as FAERS having many non-serious AEs reported from non-health care professionals while JADER has many serious AEs many serious AEs reported by medical personnel (Nomura et al., 2015;Nagai and Ishikawa, 2021).The differences of reporting areas and reporters may result in different tendencies of these databases.

Data sources
We collected the data of all GnRHas (leuprorelin, triptorelin, goserelin, buserelin, and histrelin) from FAERS and JADER from January 2004 to September 2023.Medical personnel, consumers, manufacturers, and others submit AEs and updates to these databases as spontaneous report systems (Zou et al., 2023b).From JADER, this study defined AEs using the PTs from the standardized Medical Dictionary for Regulatory Activities/ Japanese version (MedDRA/J 26.0).The data files of FAERS and JADER databases are available from their official websites (https://

Data extraction and descriptive analysis
We searched the disproportionality signals of GnRHas and their types in medical subject headings [MeSH] in Supplementary Table S1 from FAERS and JADER.We removed duplicate reports sharing the same identifier number from the demographic file and conducted an interlinkage of the reaction file with MedDRA using the PT code (Zou et al., 2023b).All data were imported into SAS software (v9.4), with the primary id as the primary link field (primary key) between different data files-patient demographic file  (Shu et al., 2023a).
We screened cases by generic names and trade names (searching by MeSH in Supplementary Table S1) in the DRUG file and chose role_cod as the primary suspected (PS) in FAERS.The process of data mining is shown in Supplementary Figure S1.Because the quantity of some GnRHas (buserelin and histrelin) was too small, we ultimately only analyzed other GnRHas (leuprorelin, triptorelin, and goserelin).It is noteworthy that the serious outcomes included death, threats to life, hospitalization, disability, and other serious outcomes (Shu et al., 2022).We thus performed a statistical analysis of serious vs. non-serious (Burk et al., 2023).

Clinical prioritization of signals
According to the designated medical event (DME) and important medical event (IME) lists from the European Medicines Agency (EMA), we created a semiquantitative score method to rank the significant disproportionality PTs in order to display special AEs (Shu et al., 2023b).GnRHas, gonadotropin-releasing hormone analogues; FAERS, FDA, adverse event reporting system; JADER, Japanese adverse drug event report; RIPPI, required intervention to prevent permanent impairment/damage; Q, quarter; NA, Not Applicable (for relevant criterias).Signal strength of adverse events of GnRHas at the SOC level from FAERS database.-, showed a negative signal (aROR 025 ≤ 1 and IC 025 ≤ 0); GnRHas, gonadotropin-releasing hormone analogs; SOC, system organ class; FAERS, FDA Adverse Event Reporting System; N, number of target adverse events; Leu, leuprolide; Tir, triptorelin; Gos, goserelin; aROR, adjusted reporting odds ratio; IC 025 , adjusted lower limit of 95% confidence interval of the information component of BCPNN; BCPNN, Bayesian confidence propagation neural network.

Statistical analysis
The adjusted reporting odds ratio (aROR) and information component (IC) of Bayesian confidence propagation neural network (BCPNN), two of the algorithms used in the disproportionality analysis, were based on the 2 × 2 table calculation principle in Supplementary Table S1 (Nagai and Ishikawa, 2021;Zou et al., 2023a;Jain et al., 2023).For the sake of robustness, statistical shrinkage transformation was performed, with the calculation formulas for aROR and IC after transformation displayed in Supplementary Table S1 (Noren et al., 2013;Chen et al., 2021).We used the following statistical methods to observe the value of P: Pearson's chi-squared (χ 2 ) test, Fisher's exact test, and Mann-Whitney U test (Sahai and Khurshid, 1995;Chau et al., 2017;FIGURE 2 Signal strength of the same adverse events of GnRHas at the PT level from FAERS database.-, showed a negative signal (aROR 025 ≤ 1 or IC 025 ≤ 0); p < 0.05, showed the significant difference by Pearson χ 2 test.GnRHas, gonadotropin-releasing hormone analogs; SOC, system organ class; PT, preferred term; FAERS, FDA Adverse Event Reporting System; N, cases of target adverse events; Leu, leuprolide; Tir, triptorelin; Gos, goserelin; aROR, adjusted reporting odds ratio; IC 025 , adjusted lower limit of 95% confidence interval of the information component of BCPNN; BCPNN, Bayesian confidence propagation neural network.Shi et al., 2023).The time-to-onset of adverse events used the formula Time-to-onset = Event onset date (EVENT_DT) -Therapy start date (START_DT), while we deleted missing or unreasonable data like the negative number of time-to-onset (24).

Signals of same preferred terms from FAERS
Figure 2 showed the same PTs (84 PTs from 15 SOCs) of GnRHas (Leu, Tri, and Gos) from FAERS, comparing the statistical significance of their signal strength by Pearson χ 2 test.To facilitate analysis of this data, the negative signals were marked "-".In blood system disorders, Leu and Gos showed stronger PTs signals, including retroperitoneal lymphadenopathy, neutropenia, and lymphadenopathy.In cardiac disorders, suspected PT of cardiac failure (Gos) detected the stronger signal (aROR 1.73, 95% CI 1.20-2.51).In the PT of death, the order of signal from strong to weak is Gos (aROR 7.90, 95% CI 7.46-8.37),Leu (aROR 2.98, 95% CI 2.91-3.06),and Tri (aROR 1.51, 95% CI 1.31-1.75).In hepatobiliary disorders, Leu and Gos showed stronger PTs signals than hepatitis fulminant, jaundice, and liver disorder.In musculoskeletal and connective tissue disorders, partial PTs only showed Leu having positive signals as back pain, extreme pain, muscle spasms, myalgia, and fibromyalgia.Moreover, two PTs (polyarthritis and polymyositis) were observed to be significantly associated with Tri.
In metabolic and nutrition disorders, only Leu showed a positive signal for diabetes mellitus (aROR 1.26, 95% CI 1.12-1.42).In the nervous system and psychiatric disorders, seven PTs showed a unique and positive signal for Leu involving migraine, memory impairment, hypoaesthesia, amnesia, dementia, sciatica, and insomnia.In renal and urinary disorders, the dysuria signal of Leu was larger than that of Gos (aROR 3.72 vs. 2.06, p < 0.05).In interstitial lung disease and pleural effusion, Gos (aROR 8.75 and 2.54) showed the largest signals.In skin disorders, Tri detected the largest signals, including abnormal hair growth, acne, abnormal skin odor, and seborrhea.Moreover, hot flush of different GnRHas also showed different aROR values, and Leu had the highest value of IC 025 (5.34), followed by Gos (IC 025 , 3.81) and Tri (IC 025 , 2.98).

Sensitivity analyses of GnRHas from FAERS
We performed sensitivity analyses (excluding all concomitant medications) of GnRHas from FAERS in Supplementary Table S3.Out of total 312 PTs, 34 PTs showed the significant differences (p < 0.05), such as dysuria, pollakiuria, urinary retention, hematuria, and nocturia.Overall, other results were largely similar and consistent  with the analysis that included all concomitant medications based on the aROR for GnRHas.
As shown in Figure 4 (excluding PTs caused by indications, operations, and unqualified products), Tri and Leu (FAERS) presented the greatest spectrum (IC 025 > 3.0), with a total of 11 and 10 strong GnRHas-induced signals (12 and 20 medium signals) detected, ranging from endocrine disorders to vascular disorders, following by Gos (one strong and 18 medium signals) and Leu-JADER (three strong and nine medium signals).In Figure 4, the suspicious PTs of Leu were obviously concentrated in endocrine disorders (pituitary hemorrhage [IC 025 3.74] and pituitary apoplexy [IC 025 3.14]), metabolism and nutrition disorders (marasmus [IC 025 3.14

Onset time of GnRHas-related AEs
Because the effective onset-time of Leu-JADER was too short to calculate, we only detected the GnRHas (Leu, Tri, and Gos) from the FAERS database.We collected the onset times of GnRHasassociated AEs from FAERS (Supplementary Figure S2).The onset times of adverse events of Leu and Tri were highly similar.The median onset time of GnRHas (Leu, Tri, and Gos) was 23 days (0, 298), 22 days (0, 181), and 217 days (29, 706), as median (Q1, Q3).

Discussion
To the best of our knowledge, we were the first to mine GnRHas data from the FAERS and JADER databases.Juan Tamargo et al. achieved greater understanding of the differences in the genetic variants of drug-metabolizing enzymes (DMEs) and transporters that determine the differences in the exposure, efficacy, and safety of cardiovascular drugs between races/ethnicities (Tamargo et al., 2022).Our study showed that the most commonly reported and newest signals of GnRHas were found at the SOC and PT levels in two databases.
In our disproportionality analysis, many organs or tissues could have been under the influence of GnRHas at SOC levels.Tri (FAERS) seemed to have the broadest and strongest signals of SOC, such as for reproductive system disorders (ROR 8.44, IC 025 2.92), product issues (aROR 6.97, IC 025 2.67), endocrine disorders (aROR 4.46, IC 025 1.67), psychiatric disorders (aROR 1.99, IC 025 0.88), social circumstances (aROR 3.72, IC 025 1.39), and skin disorders (aROR 1.17, IC 025 0.07).Unlike JAERS, Leu from JADER had also the broadest aROR of SOC, although many of the values are not the largest and had the characteristic SOCs, such as cardiac disorders (aROR 1.48, IC 025 0.29) and eye disorders (aROR 2.53, IC 025 0.63).The reason for this might be that most reports were by medical personnel in Japan and most by public in the United States (Table 1).For example, for hot flush in Figure 4, three GnRHas (Leu, Tri, and Gos from FAERS) showed strong signals (IC 025 ,5.34,2.98,and 3.81) but Leu (JADER) showed a weak signal (IC 025 , 1.38).
Furthermore, we found that some PTs might result in serious outcomes, with statistically significant differences observed between severe and non-severe cases (p < 0.001) in different GnRHas, such as hot flush, osteoporosis, and dementia.A prospective, single-center, single-arm, open label study of the long-term use of Tri showed an increased risk of developing osteopenia after 12 months of treatment (Alshehre et al., 2020).A 4-year interventional case-control study reported a case of metatarsal fracture (Dotremont et al., 2023).Similarly, we also found the clinical priority for femoral neck fracture caused by Tri (aROR 10.75, 95% CI 6.23-18.54)was moderate.
It is noteworthy that the aROR of dementia (Alzheimer's type, n = 106) was 56.47 (95%, 46.56-68.47)with IC 025 (5.50, a strong signal) caused by Tri.The clinical priority of the PT showed a moderate (Zondervan et al., 2020) signal.A cohort study of 23,651 patients with newly diagnosed prostate cancer showed the use of antiandrogen monotherapy was associated with an increased risk of dementia or Alzheimer's disease (AD) (Huang et al., 2020).
Interestingly, even for the same PTs, the aROR values of different GnRHas were quite different.In Figures 2 and 3, only positive signals showed in the forest plot.A meta-analysis of the use of GnRHas for the treatment of endometriosis revealed that the most frequently reported adverse events included vaginal dryness, hot flushes, headaches, muscle cramps (myalgia), sleep disturbance (insomnia), altered libido, weight gain, bone loss, and acne (Veth et al., 2023;Zheng et al., 2023).
A clinical study of leuprolide acetate 6-month depot showed that eight subjects in the study encountered AEs that were associated with diabetes mellitus (n = 2), elevations in serum glucose (n = 5), or hypoglycemia (n = 1) (Spitz et al., 2012).Another study involving girls with idiopathic CPP treated with GnRHas also demonstrated a deterioration in glucose metabolism during GnRHas treatment, with complete restoration observed afterward; this effect was independent of pre-treatment body mass index (BMI) (Bruzzi et al., 2022).Coincidentally, we found that only leuprolide had a positive signal for diabetes mellitus (aROR 1.26, 95% CI 1.12-1.42,IC 025 0.14) in FAERS.Interestingly, in Supplementary Table S2, compared with FAERS, leuprolide (JADER) had stronger signals in metabolism disorders such as increased blood glucose (aROR 2.59 vs. no-significant), increased blood triglycerides (aROR 3.48 vs. no-significant), diabetes mellitus (aROR 11.43 vs. 1.26),and marasmus (aROR 45.03 vs. 14.58).An observational study of 37,443 population-based men showed that androgen deprivation therapy with GnRHa was associated with an increased risk of diabetes (Keating et al., 2010).In a mechanistic study of fat accumulation, Dr Hefeng Huang found that FSH downregulated aquaporin 7 (AQP7) expression and glycerol efflux function in mature adipocytes of post-menopausal women and ovariectomized (OVX) mice (Chen et al., 2020).
Extended periods of high hormone concentration might potentially lead to hormone-related adverse events (AEs).The reason for the difference might be the different signaling pathways, structure, and dosage form of GnRHas.Robert P Millar et al. (2008) found that the effects of various GnRHas were notably distinct in relation to their impact on the pituitary gonadotrope, as they engage different signaling pathways (Millar et al., 2008).The GnRH receptor can adopt different conformations, each exhibiting varying selectivity for GnRHas and intracellular signaling protein complexes (Millar et al., 2008).
Even if both GnRHas acted on the reproductive system (Supplementary Table S2), their effects were different.In the reproductive system, prostatic GnRH-receptors appeared to be different from the pituitary, endometrium, and ovary, which showed a lower binding affinity for GnRH and its analogs (Limonta et al., 1992;Dondi et al., 1994;Casati et al., 2023).Thus, the adverse effects of GnRHa on women and men might be different.However, it is worth noting that when concomitant medications were removed in a sensitivity analysis, the aROR of GnRHa from FAERS were largely in keeping with the results from the primary analysis (Supplementary Table S3).
Finally, we collected the onset time of GnRHas in Supplementary Figure S2.The onset-time curves of adverse events caused by Leu and Tri were highly similar, as median (Q1, Q3) (23 days [0, 298] and 22 days [0, 181]).The results might be caused by the similar protein structure of Leu and Tri, which were derived from the native GnRH by substitution of a L-glycine in position 6 (Warner et al., 1983;Lahlou, 2005).
Our study also had certain limitations.First, because of the concomitant medications, missing, incomplete and repetitive reports, disproportionality analysis alone cannot prove causation or measure incidence, and specific limitations, including confounding, reporting bias and efforts to mitigate them.Second, the number of total cases had large differences between the two databases.JADER is a database limited to individual case reports, which reports serious cases individually, while FAERS also includes periodic reports that collectively report non-serious cases collected over a period of time (Noguchi et al., 2021).However, we applied the statistical shrinkage transformation for the sake of robustness to minimize this bias as much as possible.Third, in this study, we did not conduct sensitivity analyses on the influence of the indications of GnRHas.Notably, even if the number of FAERS reports is limited to data from Japan and the United States, the available Japanese data account for less than 5% of the total United States data (Nawa et al., 2021).
Due to the distinct signaling pathways, further investigation into GnRH analogs (GnRHas) held significant value for the fields of pharmacovigilance and pharmacodynamics, especially diverse racial populations.We anticipated that our analysis, utilizing spontaneous adverse drug event report databases, will serve as a valuable contribution to future studies in this domain.

Conclusion
This is the first study to analyze GnRHas from the FAERS and JADER databases comprehensively and systematically.The continuous monitoring of drug safety profiles in real-world scenarios is imperative.Moreover, our study provided the differences of GnRHas from FAERS and JADER.

TABLE 2
Differences in clinical characteristics of serious and non-serious reports of each GnRHa (n ≥ 30).

TABLE 2 (
Continued) Differences in clinical characteristics of serious and non-serious reports of each GnRHa (n ≥ 30).

TABLE 2 (
Continued) Differences in clinical characteristics of serious and non-serious reports of each GnRHa (n ≥ 30).

TABLE 2 (
Continued) Differences in clinical characteristics of serious and non-serious reports of each GnRHa (n ≥ 30).χ2 statistic of the Yates's correction for continuity.Proportions were compared using Yates's correction for continuity.
gAEs listed above had significant signal strengths.NA, Not Applicable (for relevant criterias).N: cases of serious/non-serious adverse events.GnRHa, gonadotrophin-releasing hormone analog.p-value <0.05 was considered statistically significant.a χ2 statistic of the Pearson chi-squared test.b Proportions were compared using the Pearson χ2 test.c Z statistic of the Mann-Whitney U test.d Mann-Whitney U test. e Proportions were compared using Fisher's exact test.f g

TABLE 3
Signal strength and clinical priority assessing results of suspicious PTs (unlisted in instructions).

TABLE 3 (
Continued) Signal strength and clinical priority assessing results of suspicious PTs (unlisted in instructions).

TABLE 3 (
Continued) Signal strength and clinical priority assessing results of suspicious PTs (unlisted in instructions).

TABLE 3 (
Continued) Signal strength and clinical priority assessing results of suspicious PTs (unlisted in instructions).

TABLE 3 (
Continued) Signal strength and clinical priority assessing results of suspicious PTs (unlisted in instructions).PTs, preferred terms; aROR, adjusted reporting odds ratio; CI, confidence interval; IME, important medical event; DME, designated medical event; NA, not applicable (for relevant criteria); n, number of cases.*, showed the unlisted AEs (adverse events) in the dispensatories of GnRHas (Gonadotrophin-releasing hormone analogs).++: AEs are mainly from the FDA prescribing information, the Summary of Product Characteristics of GnRHas posted by the MHRA, Phase 2/3 RCTs, or systematic reviews, with biological plausibility.+: AEs are mainly from other clinical trials, observational studies, or case reports/series with potential biological plausibility.-, AEs only emerging from disproportionality analyses.