A Study of LY900010 in Erectile Dysfunction

The primary purpose of the study is to compare the efficacy of LY2452473 + tadalafil to tadalafil alone in improving the erectile function (EF) of men with erectile dysfunction (ED) who incompletely respond to tadalafil alone.


Eligibility Criteria:
Inclusion Criteria include:

* Ambulatory men
* History of erectile dysfunction of at least 3 months duration
* History of incomplete response to any phosphodiesterase type 5 inhibitor (PDE5i) at the maximum tolerated dose within the label
* Anticipate having the same female sexual partner throughout the duration of the study
* Are willing and able to make at least 4 sexual intercourse attempts with the female sexual partner during each 4-week segment of the study
* Agree to use birth control during the study and for 60 days after the study, unless the female partner is postmenopausal
* Agree not to use any other erectile dysfunction treatment, including herbal treatment, during the study and for 96 hours after the last dose of study drug
* Screening laboratory tests within normal limits except for testosterone
* Without a language barrier, are reliable and willing to follow study procedures
* Prostate-specific antigen (PSA) less than 10 nanograms per milliliter (ng/ml). Men with PSA greater than 4 and less than 10 ng/ml must have documentation of a negative histological biopsy of carcinoma of prostate within 12 months prior to screening

Exclusion Criteria include:

* History of penile implant
* History of no response to injection therapy for erectile dysfunction
* History of radical prostatectomy or other pelvic surgery with subsequent failure to achieve any erection
* Exhibit the presence of clinically significant penile deformity in the opinion of the investigator
* History of prior sexual legal convictions
* Bilateral hip replacements
* History of cancer within the previous 5 years, except for excised superficial lesions such as basal cell carcinoma and squamous cell carcinoma of the skin
* Chronic stable angina currently treated with long-acting nitrates
* Chronic stable angina requiring treatment with short-acting nitrates within 90 days prior to screening
* Angina occurring during sexual intercourse in the 6 months prior to screening
* Unstable angina within 6 months prior to screening
* Myocardial infarction or coronary artery bypass graft surgery within 90 days prior to screening
* Angioplasty or stent placement within 90 days prior to screening
* Congestive heart failure within 6 months prior to screening
* History of sudden cardiac arrest
* Supraventricular arrhythmia with an uncontrolled ventricular response at rest, or any history of spontaneous or induced sustained ventricular tachycardia, or use an automatic internal cardioverter-defibrillator
* An abnormality in the 12-lead electrocardiogram (ECG) that in the opinion of the investigator places the subject in an unacceptable risk for study participation
* Systolic blood pressure greater than 170 or less than 90 millimeters of mercury (mm Hg) or diastolic blood pressure greater than 100 or less than 50 mm Hg at screening
* Hepatic, renal, human immunodeficiency virus (HIV), or clinically significant active neuropsychiatric disease
* History of central nervous system injuries (including stroke or spinal cord injury) within 6 months prior to screening
* Alcohol intake of 5 units or greater per day (1 unit = 12 ounces beer, 5 ounces wine, or 1.5 ounces of 80-proof distilled spirits)
* Receiving treatment with antiandrogens or 5-alpha reductase inhibitor
* Anabolic steroids, calcitonin, oral bisphosphonates, Vitamin D greater than 50,000 international units per week (IU/week), dehydroepiandrosterone (DHEA), steroidal supplements, nutritional products intended to have weight reduction or performance enhancing effects, herbal supplements within 7 days prior to screening
* Currently treated with a potent cytochrome P450 (CYP) 3A4 inhibitor, such as systemic ketoconazole or ritonavir, or a CYP3A4 inducer such as rifampicin