Gefitinib and Methotrexate to Treat Ectopic Pregnancies with a Pre-Treatment Serum hCG 1000-10,000 IU/L: Phase II Open Label, Single Arm Multi-Centre Trial

Effectiveness of treatment options for tubal ectopic pregnancy: A systematic review and network meta-analysis

BACKGROUND

Tubal ectopic pregnancy (TEP) is a common gynaecological emergency. Several medical and surgical treatment options exist, but it is not clear which is the safest and most effective treatment.

OBJECTIVES

To compare the effectiveness of expectant, medical and surgical treatment options for TEP using a systematic review and network meta-analysis.

SEARCH STRATEGY

MEDLINE, EMBASE, and CENTRAL from inception till September 2022.

SELECTION CRITERIA

Randomised trials that evaluated any treatment option for woman with a TEP.

DATA COLLECTION AND ANALYSIS

We performed pairwise and network meta-analyses using a random effect model. We assessed the studies' risk of bias, heterogeneity and network inconsistency. We reported primarily on TEP resolution and treatment failure using relative risk (RR) and 95% confidence-intervals (CI).

MAIN RESULTS

We included 31 randomised trials evaluating ten treatments (n = 2938 women). Direct meta-analysis showed no significant benefit for using methotrexate compared to expectant management for TEP resolution. Network meta-analysis showed similar effect-size for most conservative treatment options compared to expectant management for TEP resolution (glucose intra-sac instillation vs. expectant RR 0.84, 95% CI 0.63-1.12; methotrexate intra-sac instillation vs. expectant RR 0.91, 95% CI 0.75-1.10; multi-dose methotrexate vs. expectant RR 1.00, 95% CI 0.88-1.15; prostaglandin intra-sac instillation vs. expectant RR 0.75, 95% CI 0.53-1.07; salpingotomy vs. expectant RR 0.99, 95% CI 0.84-1.16; single dose methotrexate vs. expectant RR 0.97, 95% CI 0.85-1.10; single dose methotrexate + mifepristone vs. expectant RR 1.09, 95% CI 0.89-1.33). All treatment options showed a higher risk of failure compared to salpingectomy.

CONCLUSIONS

There is insufficient evidence to support the use of any medical treatment option for TEP over expectant management.

Combination of gefitinib and methotrexate to treat tubal ectopic pregnancy (GEM3): a multicentre, randomised, double-blind, placebo-controlled trial

BACKGROUND

Tubal ectopic pregnancies can cause substantial morbidity or even death. Current treatment is with methotrexate or surgery. Methotrexate treatment fails in approximately 30% of women who subsequently require rescue surgery. Gefitinib, an epidermal growth factor receptor inhibitor, might improve the effects of methotrexate. We assessed the efficacy of oral gefitinib with methotrexate, versus methotrexate alone, to treat tubal ectopic pregnancy.

METHODS

We performed a multicentre, randomised, double-blind, placebo-controlled trial across 50 UK hospitals. Participants diagnosed with tubal ectopic pregnancy were administered a single dose of intramuscular methotrexate (50 mg/m2) and randomised (1:1 ratio) to 7 days of additional oral gefitinib (250 mg daily) or placebo. The primary outcome, analysed by intention to treat, was surgical intervention to resolve the ectopic pregnancy. Secondary outcomes included time to resolution of ectopic pregnancy and serious adverse events. This trial is registered at the ISRCTN registry, ISCRTN 67795930.

FINDINGS

Between Nov 2, 2016, and Oct 6, 2021, 328 participants were allocated to methotrexate and gefitinib (n=165) or methotrexate and placebo (n=163). Three participants in the placebo group withdrew. Surgical intervention occurred in 50 (30%) of 165 participants in the gefitinib group and in 47 (29%) of 160 participants in the placebo group (adjusted risk ratio 1·15, 95% CI 0·85 to 1·58; adjusted risk difference -0·01, 95% CI -0·10 to 0·09; p=0·37). Without surgical intervention, median time to resolution was 28·0 days in the gefitinib group and 28·0 days in the placebo group (subdistribution hazard ratio 1·03, 95% CI 0·75 to 1·40). Serious adverse events occurred in five (3%) of 165 participants in the gefitinib group and in six (4%) of 162 participants in the placebo group. Diarrhoea and rash were more common in the gefitinib group.

INTERPRETATION

In women with a tubal ectopic pregnancy, adding oral gefitinib to parenteral methotrexate does not offer clinical benefit over methotrexate and increases minor adverse reactions.

FUNDING

National Institute of Health Research.

Future Perspectives of Ectopic Pregnancy Treatment-Review of Possible Pharmacological Methods

Ectopic pregnancy, that is, a blastocyst occurring outside the endometrial cavity of the uterus, affects nearly 2% of pregnancies. The treatment of ectopic pregnancy is surgical or pharmacological. Since surgical management is associated with numerous serious side effects, conservative treatment is sought. The treatment of choice in the majority of cases is based on pharmacotherapy with methotrexate (MTX) in a single- or multi-dose regimen. Although the efficacy of methotrexate reaches between 70 and 90%, its use requires specific conditions regarding both the general condition of the patient and the characteristic features of the ectopic pregnancy. Moreover, MTX can cause severe adverse effects, including stomatitis, hepatotoxicity and myelosuppression. Therefore, clinicians and researchers are still looking for a less toxic, more effective treatment, which could prevent surgeries as a second-choice treatment. Some studies indicate that other substances might constitute a good alternative to methotrexate in the management of ectopic pregnancies. These substances include aromatase inhibitors, especially letrozole. Another promising substance in EP treatment is gefitinib, an inhibitor of EGFR tyrosine domain which, combined with MTX, seems to constitute a more effective alternative in the management of tubal ectopic pregnancies. Other substances for local administration include KCl and absolute ethanol. KCl injections used in combination with MTX may be used when foetal heart function is detected in cervical ectopic pregnancies, as well as in heterotopic pregnancy treatment. Absolute ethanol injections proved successful and safe in caesarean scar pregnancies management. Thus far, little is known about the use of those substances in the treatment of ectopic pregnancies, but already conducted studies seem to be promising.

Combination methotrexate and gefitinib: A potential medical treatment for inoperable nontubal ectopic pregnancy

Nontubal ectopic pregnancies present as a therapeutic challenge. A 35-year-old primigravida at 7 weeks gestation had a live interstitial ectopic pregnancy and contraindications to surgery. The patient was treated with a multidose methotrexate regimen combined with oral gefitinib (250 mg daily for 7 days). The peak human chorionic gonadotropin (hCG) of the patient was recorded at 19 510 IU/L and began declining from day 4 of combination therapy (day 6 of initial treatment). Successful resolution of the ectopic was demonstrated by cessation of the fetal heart by day 15 and hCG falling to 23 IU/L by day 42. A 10-year review of all nontubal ectopic pregnancies treated with methotrexate identified 46 cases, which had a comparable time to resolution to combination therapy. However, for cases where cardiac activity was present, the median time to resolution following methotrexate treatment was 64 days (47-87 days), 22 days longer than combination therapy. Combination therapy may provide a safe medical treatment for inoperable nontubal ectopic pregnancy.

A multi-centre, double-blind, placebo-controlled, randomised trial of combination methotrexate and gefitinib versus methotrexate alone to treat tubal ectopic pregnancies (GEM3): trial protocol

Background

Tubal ectopic pregnancy (tEP) is the most common life-threatening condition in gynaecology. Treatment options include surgery and medical management. Stable women with tEPs with pre-treatment serum human chorionic gonadotrophin (hCG) levels < 1000 IU/L respond well to outpatient medical treatment with intramuscular methotrexate. However, tEPs with hCG > 1000 IU/L can take significant time to resolve with methotrexate and require multiple outpatient monitoring visits. In pre-clinical studies, we found that tEP implantation sites express high levels of epidermal growth factor receptor. In early-phase trials, we found that combination therapy with gefitinib, an orally active epidermal growth factor receptor antagonist, and methotrexate resolved tEPs without the need for surgery in over 70% of cases, did not cause significant toxicities, and was well tolerated. We describe the protocol of a randomised trial to assess the efficacy of combination gefitinib and methotrexate, versus methotrexate alone, in reducing the need for surgical intervention for tEPs.

Methods and analysis

We propose to undertake a multi-centre, double-blind, placebo-controlled, randomised trial (around 70 sites across the UK) and recruit 328 women with tEPs (with pre-treatment serum hCG of 1000–5000 IU/L). Women will be randomised in a 1:1 ratio by a secure online system to receive a single dose of intramuscular methotrexate (50 mg/m²) and either oral gefitinib or matched placebo (250 mg) daily for 7 days. Participants and healthcare providers will remain blinded to treatment allocation throughout the trial. The primary outcome is the need for surgical intervention for tEP. Secondary outcomes are the need for further methotrexate treatment, time to resolution of the tEP (serum hCG ≤ 15 IU/L), number of hospital visits associated with treatment (until resolution or scheduled/emergency surgery), and the return of menses by 3 months after resolution. We will also assess adverse events and reactions until day of resolution or surgery, and participant-reported acceptability at 3 months.

Discussion

A medical intervention that reduces the need for surgery and resolves tEP faster would be a favourable treatment alternative. If effective, we believe that gefitinib and methotrexate could become standard care for stable tEPs.

Trial registration

ISRCTN Registry ISRCTN67795930. Registered 15 September 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3008-6) contains supplementary material, which is available to authorized users.