Droxidopa Drug Information

• Starting dose is 100 mg three times during the day (2.1)
• Titrate by 100 mg three times daily, up to a maximum dose of 600 mg three times daily (2.1)
• Take consistently with or without food (2.1)
• To reduce the potential for supine hypertension, elevate the head of the bed and give the last dose at least 3 hours prior to bedtime (2.1)
• Take droxidopa capsule whole (2.1) 2.1 Dosing Information The recommended starting dose of droxidopa capsules is 100 mg, taken orally three times daily: upon arising in the morning, at midday, and in the late afternoon at least 3 hours prior to bedtime (to reduce the potential for supine hypertension during sleep). Administer droxidopa capsules consistently, either with food or without food. Take droxidopa capsule whole. Titrate to symptomatic response, in increments of 100 mg three times daily every 24 to 48 hours up to a maximum dose of 600 mg three times daily (i.e., a maximum total daily dose of 1,800 mg). Monitor supine blood pressure prior to initiating droxidopa capsules and after increasing the dose. Patients who miss a dose of droxidopa capsules should take their next scheduled dose.

• The following adverse reactions with droxidopa are included in more detail in the Warnings and Precautions section of the label:
• Supine Hypertension [see Warnings and Precautions (5.1) ]
• Hyperpyrexia and Confusion [see Warnings and Precautions (5.2) ]
• May exacerbate existing ischemic heart disease, arrhythmias, and congestive heart failure [see Warnings and Precautions (5.3) ] The most common adverse reactions (>5% and ≥3% compared to placebo) are headache, dizziness, nausea, and hypertension (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Slate Run Pharmaceuticals, LCC at 1-888-341-9214 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The safety evaluation of droxidopa is based on two placebo-controlled studies 1 to 2 weeks in duration (Studies 301 and 302), one 8-week placebo-controlled study (Study 306), and two long-term, open-label extension studies (Studies 303 and 304). In the placebo-controlled studies, a total of 485 patients with Parkinson's disease, multiple system atrophy, pure autonomic failure, dopamine beta-hydroxylase deficiency, or non-diabetic autonomic neuropathy were randomized and treated, 245 with droxidopa and 240 with placebo [see Clinical Studies (14) ] . Placebo-Controlled Experience The most commonly observed adverse reactions (those occurring at an incidence of greater than 5% in the droxidopa group and with at least a 3% greater incidence in the droxidopa group than in the placebo group) in droxidopa-treated patients during the three placebo-controlled trials were headache, dizziness, nausea, and hypertension. The most common adverse reactions leading to discontinuation from droxidopa were hypertension or increased blood pressure and nausea. Table 1. Most Common Adverse Reactions Occurring More Frequently in the Droxidopa Group Study 301 and Study 302 (1 to 2 Weeks Randomized Treatment) Study 306 (8 to 10 Weeks Randomized Treatment) Placebo (N=132) n (%) Droxidopa (N=131) n (%) Placebo (N=108) n (%) Droxidopa (N=114) n (%) Headache 4 (3.0) 8 (6.1) 8 (7.4) 15 (13.2) Dizziness 2 (1.5) 5 (3.8) 5 (4.6) 11 (9.6) Nausea 2 (1.5) 2 (1.5) 5 (4.6) 10 (8.8) Hypertension 0 2 (1.5) 1 (0.9) 8 (7.0) Note: n=number of patients. Adverse reactions that were reported in greater than 5% of patients in the droxidopa group and with at least a 3% greater incidence in the droxidopa group than in the placebo group were from Study 306. Long-Term, Open-Label Trials with Droxidopa In the long-term, open-label extension studies, a total of 422 patients, mean age 65 years, were treated with droxidopa for a mean total exposure of approximately one year. The commonly reported adverse events were falls (24%), urinary tract infections (15%), headache (13%), syncope (13%), and dizziness (10%). 6.2 Postmarketing Experience The following adverse reactions have been identified during post-approval use of droxidopa. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Cardiac Disorders : Chest pain Eye Disorders : Blurred vision Gastrointestinal Disorders : Pancreatitis, abdominal pain, vomiting, diarrhea General Disorders and Administration Site Conditions : Fatigue Nervous System Disorders : Cerebrovascular accident Psychiatric Disorders : Psychosis, hallucination, delirium, agitation, memory disorder

Drugs that Increase Blood Pressure Administering droxidopa in combination with other agents

that increase blood pressure (e.g., norepinephrine, ephedrine, midodrine, and triptans) would be expected to increase the risk for supine hypertension.

Parkinson’s Medications Dopa-decarboxylase inhibitors may require dose adjustments for droxidopa. 7.3 Non-selective

MAO Inhibitors The concomitant use of selective MAO-B inhibitors, such as rasagiline or selegiline, was permitted in the droxidopa clinical trials. However, based on mechanism of action, the use of non-selective MAO inhibitors and linezolid should be avoided as there is a potential for increased blood pressure when taken with droxidopa.

Pregnancy Risk Summary There are no available data on use of droxidopa in pregnant women and risk of major birth defects or miscarriage. Droxidopa did not produce significant reproductive toxicity in pregnant female rats or rabbits or in their fetuses. However, when pregnant female rats were dosed during days 7-17 of gestation (the period of fetal organogenesis) with doses of droxidopa corresponding to 0.3, 1 and 3 times the maximum recommended daily dose of 1,800 mg in a 60 kg patient, based on body surface area, and when their male and female offspring (who were exposed only during fetal life) were subsequently bred, the female offspring exhibited a dose-dependent reduction in the number of live fetuses across all three doses and an increased number of embryonic/fetal deaths at the two higher doses (see Data). The estimated background risk of major birth defects and miscarriage in the indicated population is unknown.

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Data Animal Data During a multigenerational reproductive toxicity study in rats, pregnant females were dosed during days 7-17 of gestation (the period of fetal organogenesis) with doses of droxidopa corresponding to 0.3, 1 and 3 times the maximum recommended daily dose of 1,800 mg in a 60 kg patient. Reduced weight gain, renal lesions, and a small number of deaths were observed in females treated with the two higher doses.

When their male and female offspring (who were exposed to droxidopa only during fetal life) were subsequently bred, the female offspring exhibited a dose-dependent reduction in the number of live fetuses across all three doses and an increased number of embryonic/fetal deaths at the two higher doses.

Pediatric Use The safety and effectiveness of droxidopa in pediatric patients have not been established.

Droxidopa is contraindicated in patients who have a history of hypersensitivity to the drug or its ingredients. History of hypersensitivity to the drug or its ingredients

Symptoms

There have been cases of overdose reported during postmarketing surveillance. A patient ingested 7,700 mg of droxidopa and experienced a hypertensive crisis that resolved promptly with treatment. Another patient treated with a total daily dose of 2,700 mg of droxidopa experienced hypertension and an intracranial hemorrhage.

Treatment

There is no known antidote for droxidopa overdosage. In case of an overdose that may result in an excessively high blood pressure, discontinue droxidopa and treat with appropriate symptomatic and supportive therapy. Counsel patients to remain in a standing or seated position until their blood pressure drops below an acceptable limit.