Tramadol Versus Placebo in the Management of Postoperative Pain Following Bunionectomy

Key Inclusion Criteria: * The patient is male or female 18-75 years of age undergoing unilateral first metatarsal bunionectomy surgery * Willing to give consent and able to understand the study procedures * Female patients must be of non-childbearing potential or be practicing a highly effective contraception * The patient must be willing to be housed in a healthcare facility and able to receive parenteral analgesia for at least 72 hours after surgery. * The patient meets definition of American Society of Anesthesiologists (ASA) Physical Class 1, or 2. Exclusion Criteria: * Patient is not expected to receive a continuous infusion nerve block as described in the Post-Op anesthetic procedures protocol * Patient is undergoing bilateral or revision bunionectomy surgery * The patient has allergy or hypersensitivity (or is intolerant) to opioids or tramadol The patient has known physical dependence on opioids * The patient has taken other prior/concurrent chronic medications that have not been at a stable dose for at least 2 weeks prior to screening * The patient is taking herbal or dietary supplements or medications that are moderate or strong inhibitors of CYP2D6 or CYP3A4 or inducers of CYP3A4 * The patient has taken monoamine oxidase (MAO) inhibitors, trazodone, or cyclobenzaprine within 14 days prior to surgery * The patient cannot be withdrawn from medications (at least 7 days prior to surgery) that may lower the seizure threshold (e.g. anti-psychotic agents, MAOI inhibitors) or which increase serotonergic tone (e.g. selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, triptans). * The patient has a history of epilepsy, or is known to be susceptible to seizures * The patient has a history of Long QT Syndrome or a relative with this condition * The patient has expressed suicidal ideation or is considered to be at risk of suicide. * The patient is morbidly obese (body mass index \[BMI\] ≥ 40 kg/m2) or has documented sleep apnea requiring pharmacological or device intervention. * Clinically significant abnormalities in the judgement of the Investigator * The patient was administered an investigational product within 30 days prior to Screening. * The patient has previously participated in a clinical study with AVE-901.