ER/Estrogen receptor. Estradiol enanthate is a long-acting estrogen ester used in combination with dihydroxyprogesterone acetophenide (DHPA) as a once-monthly injectable contraceptive. No specific binding affinity or potency data (e.g., IC₅₀, EC₅₀) were reported in this study. [1]

Contraceptive Efficacy: In a prospective, open, randomized study of 365 adolescents (aged 14–19 years) using a monthly injectable contraceptive containing estradiol enanthate 10 mg and dihydroxyprogesterone acetophenide 150 mg, a total of 5 pregnancies occurred over 12 cycles of use: 2 in Group 1 (injection every 30 ± 3 days) and 3 in Group 2 (injection on days 7–10 of the menstrual cycle). The difference was not statistically significant (p = 0.48). Life table analysis showed cumulative pregnancy rates of 1.4% and 1.7% in Groups 1 and 2, respectively. [1]
Bleeding Pattern: The mean duration of bleeding episodes was 5.8 ± 1.7 days in Group 1 and 5.5 ± 1.2 days in Group 2 (p = 0.187). The mean cycle length was 28.7 ± 4.1 days in Group 1 and 26.6 ± 3.8 days in Group 2 (p < 0.001). Spotting episodes ranged from 2.0 ± 1.0 to 3.5 ± 6.0 days in Group 1 and 2.3 ± 1.2 to 3.6 ± 2.3 days in Group 2 over 90-day segments, with no significant differences between groups. [1]
Treatment Completion: Of 365 enrolled subjects, 266 (73%) completed the 12-month treatment: 130/186 (70%) in Group 1 and 136/179 (76%) in Group 2 (p = 0.21). Mean time in the study was 7.64 ± 0.5 months in Group 1 and 7.55 ± 0.4 months in Group 2. [1]
Introduction: This study compared two regimens of a monthly injectable contraceptive containing dihydroxyprogesterone acetophenide 150 mg and estradiol enanthate 10 mg (Perlutan) over 12 cycles of use. Methods: Three hundred sixty-five adolescents were randomized into two groups. The patients in Group 1 received an initial injection of Perlutan on the 1st-5th day of their menstrual cycle and subsequent injections every 30 +/- 3 days, whereas those in Group 2 followed the traditional schedule of administration in which the first injection is administered between Days 7 and 10 of their menstrual cycle and subsequent injections 7-10 days after Day 1 of withdrawal bleeding. This schedule may result in an irregularity in the timing of injections. Results: No significant difference was found between the two groups regarding tolerability or pregnancy (two in Group 1 and three in Group 2). Conclusion: Monthly administration limits the annual number of injections to a maximum of 12, thus frequently reducing the total annual dose while maintaining efficacy and tolerability similar to those obtained with the traditional regimen.[1]

Study Design: This was a prospective, open, randomized clinical study conducted at six research centers in Brazil. A total of 365 female adolescents aged 14–19 years were enrolled and randomized into two groups. [1]

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Dosing Regimen: Estradiol enanthate (10 mg) was administered intramuscularly as part of a combination injectable contraceptive (Perlutan®) containing dihydroxyprogesterone acetophenide 150 mg. Group 1 received the first injection between days 1–5 of the menstrual cycle, with subsequent injections every 30 ± 3 days. Group 2 received the first injection between days 7–10 of the menstrual cycle, with subsequent injections scheduled 7–10 days after the first day of withdrawal bleeding. All injections were given deeply intramuscularly. [1]
Duration: The study duration was 12 cycles (approximately 12 months) of contraceptive use. [1]
Exclusion Criteria: Patients were excluded if they had used any hormonal contraception in the preceding 3–8 months, had known neoplastic disease, serious hepatopathy, kidney insufficiency, hypersensitivity to any component, were pregnant or lactating, amenorrheic, or had contraindications to hormonal contraception. [1]
Monthly injectable steroid contraceptives which contained the long-acting progestogen dihydroxyprogesterone acetofenide plus a shorter-acting estrogen (usually estradiol enanthate) were used by women in two of the countries (Chile and Mexico) from which data were collected. In preliminary analyses of data from Chile (1979-1983), a strong association was observed between use of these products and invasive cervical cancer. Therefore, three additional data sets from these two countries were analyzed in further detail for this report. Analyses of additional data from Chile on invasive cervical cancer (1983-1985) and cervical carcinoma in situ (1979-1986) and of data on invasive cervical cancer from Mexico (1979-1986) failed to confirm the initially observed association. The original finding was probably due to chance, but a causal interpretation cannot be confidently ruled out, and additional studies are warranted.[2]

Adverse Events: The incidence of nonserious adverse events possibly related to the study drug was 26.9% in Group 1 and 20.7% in Group 2 (p = 0.22). Four serious adverse events were reported (influenza-like symptoms, pneumonia, cholecystectomy, and acute diarrhea), but none were considered by investigators to be related to the study medication. [1]
Weight Change: Mean body weight increased by 1.1 kg in Group 1 and 0.9 kg in Group 2 over the study duration (p = 0.931). The weight change was not significantly different between groups. [1]
Blood Pressure and Pulse Rate: No statistically significant changes in systolic blood pressure, diastolic blood pressure, or pulse rate were observed in either group during the study. [1]
Dysmenorrhea: There was no difference between the two groups regarding the occurrence of moderate to severe dysmenorrhea, reported by 24/175 patients in Group 1 and 23/175 in Group 2. [1]
Discontinuation Reasons: Discontinuation due to bleeding problems occurred in 0.7% of Group 1 and 2.0% of Group 2 (p not significant). Discontinuation due to personal reasons was 7.1% in Group 1 and 1.3% in Group 2 (p < 0.05). [1]

[1]. Comparison of two regimens of a monthly injectable contraceptive containing dihydroxyprogesterone acetophenide and estradiol enanthate. Contraception. 2006;73(3):249-252.

[2]. Monthly injectable steroid contraceptives and cervical carcinoma. Am J Epidemiol. 1989;130(2):237-247.

Estradiol heptaate is a steroidal ester.

C25H36O3

384.55

384.266

4956-37-0

Estradiol;50-28-2;Estradiol (cypionate);313-06-4;Estradiol benzoate;50-50-0

21070

White to off-white solid powder

1.1±0.1 g/cm3

509.5±50.0 °C at 760 mmHg

94-96ºC

197.1±22.9 °C

0.0±1.4 mmHg at 25°C

1.560

7.68

1

3

7

28

546

5

CCCCCCC(=O)O[C@H]1CC[C@@H]2[C@@]1(CC[C@H]3[C@H]2CCC4=C3C=CC(=C4)O)C

RFWTZQAOOLFXAY-BZDYCCQFSA-N

InChI=1S/C25H36O3/c1-3-4-5-6-7-24(27)28-23-13-12-22-21-10-8-17-16-18(26)9-11-19(17)20(21)14-15-25(22,23)2/h9,11,16,20-23,26H,3-8,10,12-15H2,1-2H3/t20-,21-,22+,23+,25+/m1/s1

[(8R,9S,13S,14S,17S)-3-hydroxy-13-methyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-17-yl] heptanoate

ESTRADIOL ENANTHATE; 4956-37-0; Oestradiol 17-heptanoate; Estradiol Enantate; Estradiol 17-heptanoate; Estradiol enanthate [USAN]; SQ 16,150; PAP315WZIA;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: 125 mg/mL (325.06 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)