Oxycodone Hydchloride

INDICATIONS AND USAGE Oxycodone hydrochloride tablets are an immediate-release oral formulation of oxycodone hydrochloride indicated for the management of moderate to severe pain where the use of an opioid analgesic is appropriate.

DOSAGE AND ADMINISTRATION Oxycodone hydrochloride tablets are intended for the management of moderate to severe pain in patients who require treatment with an oral opioid analgesic. The dose should be individually adjusted according to severity of pain, patient response and patient size. If the pain increases in severity, if analgesia is not adequate, or if tolerance occurs, a gradual increase in dosage may be required. Patients who have not been receiving opioid analgesics should be started on oxycodone hydrochloride tablets in a dosing range of 5 to 15 mg every 4 to 6 hours as needed for pain. The dose should be titrated based upon the individual patient's response to their initial dose of oxycodone hydrochloride tablets. Patients with chronic pain should have their dosage given on an around-the-clock basis to prevent the reoccurrence of pain rather than treating the pain after it has occurred. This dose can then be adjusted to an acceptable level of analgesia taking into account side effects experienced by the patient. For control of severe chronic pain, oxycodone hydrochloride tablets should be administered on a regularly scheduled basis, every 4 to 6 hours, at the lowest dosage level that will achieve adequate analgesia. As with any potent opioid, it is critical to adjust the dosing regimen for each patient individually, taking into account the patient's prior analgesic treatment experience. Although it is not possible to list every condition that is important to the selection of the initial dose of oxycodone hydrochloride tablets, attention should be given to: 1) the daily dose, potency, and characteristics of a pure agonist or mixed agonist/antagonist the patient has been taking previously, 2) the reliability of the relative potency estimate to calculate the dose of oxycodone needed, 3) the degree of opioid tolerance, 4) the general condition and medical status of the patient, and 5) the balance between pain control and adverse experiences. Conversion from Fixed-Ratio Opioid/Acetaminophen, Opioid/Aspirin, or Opioid/Nonsteroidal Combination Drugs When converting patients from fixed ratio opioid/non-opioid drug regimens a decision should be made whether or not to continue the non-opioid analgesic. If a decision is made to discontinue the use of non-opioid analgesic, it may be necessary to titrate the dose of oxycodone hydrochloride tablets in response to the level of analgesia and adverse effects afforded by the dosing regimen. If the non-opioid regimen is continued as a separate single entity agent, the starting dose oxycodone hydrochloride tablets should be based upon the most recent dose of opioid as a baseline for further titration of oxycodone. Incremental increases should be gauged according to side effects to an acceptable level of analgesia. Patients Currently on Opioid Therapy If a patient has been receiving opioid-containing medications prior to taking oxycodone hydrochloride tablets, the potency of the prior opioid relative to oxycodone should be factored into the selection of the total daily dose (TDD) of oxycodone. In converting patients from other opioids to oxycodone hydrochloride tablets close observation and adjustment of dosage based upon the patient's response to oxycodone hydrochloride tablets is imperative. Administration of supplemental analgesia for breakthrough or incident pain and titration of the total daily dose of oxycodone hydrochloride tablets may be necessary, especially in patients who have disease states that are changing rapidly. Maintenance of Therapy Continual re-evaluation of the patient receiving oxycodone hydrochloride tablets is important, with special attention to the maintenance of pain control and the relative incidence of side effects associated with therapy. If the level of pain increases, effort should be made to identify the source of increased pain, while adjusting the dose as described above to decrease the level of pain. During chronic therapy, especially for non-cancer-related pain (or pain associated with other terminal illnesses), the continued need for the use of opioid analgesics should be reassessed as appropriate. Cessation of Therapy When a patient no longer requires therapy with oxycodone hydrochloride tablets or other opioid analgesics for the treatment of their pain, it is important that therapy be gradually discontinued over time to prevent the development of an opioid abstinence syndrome (narcotic withdrawal). In general, therapy can be decreased by 25% to 50% per day with careful monitoring for signs and symptoms of withdrawal (see DRUG ABUSE AND DEPENDENCE section for description of the signs and symptoms of withdrawal). If the patient develops these signs or symptoms, the dose should be raised to the previous level and titrated down more slowly, either by increasing the interval between decreases, decreasing the amount of change in dose, or both. It is not known at what dose of oxycodone hydrochloride tablets that treatment may be discontinued without risk of the opioid abstinence syndrome.

WARNINGS Respiratory Depression Respiratory depression is the chief hazard from all opioid agonist preparations. Respiratory depression occurs most frequently in elderly or debilitated patients, usually following large initial doses in non-tolerant patients, or when opioids are given in conjunction with other agents that depress respiration. Oxycodone hydrochloride tablets should be used with extreme caution in patients with significant chronic obstructive pulmonary disease or cor pulmonale, and in patients having substantially decreased respiratory reserve, hypoxia, hypercapnia, or pre-existing respiratory depression. In such patients, even usual therapeutic doses of oxycodone hydrochloride tablets may decrease respiratory drive to the point of apnea. In these patients alternative non-opioid analgesics should be considered, and opioids should be employed only under careful medical supervision at the lowest effective dose. Hypotensive Effect Oxycodone hydrochloride tablets, like all opioid analgesics, may cause severe hypotension in an individual whose ability to maintain blood pressure has been compromised by a depleted blood volume, or after concurrent administration with drugs such as phenothiazines or other agents which compromise vasomotor tone. Oxycodone hydrochloride tablets may produce orthostatic hypotension in ambulatory patients. Oxycodone hydrochloride tablets, like all opioid analgesics, should be administered with caution to patients in circulatory shock, since vasodilatation produced by the drug may further reduce cardiac output and blood pressure. Head Injury and Increased Intracranial Pressure The respiratory depressant effects of narcotics and their capacity to elevate cerebrospinal fluid pressure may be markedly exaggerated in the presence of head injury, other intracranial lesions or a pre-existing increase in intracranial pressure. Furthermore, narcotics produce adverse reactions which may obscure the clinical course of patients with head injuries.

CONTRAINDICATIONS Oxycodone hydrochloride tablets are contraindicated in patients with known hypersensitivity to oxycodone, or in any situation where opioids are contraindicated. This includes patients with significant respiratory depression (in unmonitored settings or the absence of resuscitative equipment) and patients with acute or severe bronchial asthma or hypercarbia. Oxycodone hydrochloride tablets are contraindicated in any patient who has or is suspected of having paralytic ileus.

ADVERSE REACTIONS Oxycodone hydrochloride tablets have been evaluated in open label clinical trials in patients with cancer and nonmalignant pain. Oxycodone hydrochloride tablets are associated with adverse experiences similar to those seen with other opioids. Serious adverse reactions that may be associated with oxycodone hydrochloride tablets therapy in clinical use are those observed with other opioid analgesics and include: respiratory depression, respiratory arrest, circulatory depression, cardiac arrest, hypotension, and/or shock (see OVERDOSAGE , WARNINGS ). The less severe adverse events seen on initiation of therapy with oxycodone hydrochloride tablets are also typical opioid side effects. These events are dose dependent, and their frequency depends on the clinical setting, the patient's level of opioid tolerance, and host factors specific to the individual. They should be expected and managed as a part of opioid analgesia. The most frequent of these include nausea, constipation, vomiting, headache, and pruritus. In many cases the frequency of adverse events during initiation of opioid therapy may be minimized by careful individualization of starting dosage, slow titration and the avoidance of large rapid swings in plasma concentration of the opioid. Many of these adverse events will abate as therapy is continued and some degree of tolerance is developed, but others may be expected to remain throughout therapy. In all patients for whom dosing information was available (n=191) from the open-label and double-blind studies involving oxycodone hydrochloride tablets, the following adverse events were recorded in patients treated with oxycodone hydrochloride tablets with an incidence ≥ 3%. In descending order of frequency they were: nausea, constipation, vomiting, headache, pruritus, insomnia, dizziness, asthenia, and somnolence. The following adverse experiences occurred in less than 3% of patients involved in clinical trials with oxycodone: Body as a Whole – abdominal pain, accidental injury, allergic reaction, back pain, chills and fever, fever, flu syndrome, infection, neck pain, pain, photosensitivity reaction, and sepsis. Cardiovascular – deep thrombophlebitis, heart failure, hemorrhage, hypotension, migraine, palpitation, and tachycardia. Digestive – anorexia, diarrhea, dyspepsia, dysphagia, gingivitis, glossitis, and nausea and vomiting. Hemic and Lymphatic – anemia and leukopenia. Metabolic and Nutritional – edema, gout, hyperglycemia, iron deficiency anemia and peripheral edema. Musculoskeletal – arthralgia, arthritis, bone pain, myalgia and pathological fracture. Nervous – agitation, anxiety, confusion, dry mouth, hypertonia, hypesthesia, nervousness, neuralgia, personality disorder, tremor, and vasodilation. Respiratory – bronchitis, cough increased, dyspnea, epistaxis, laryngismus, lung disorder, pharyngitis, rhinitis, and sinusitis. Skin and Appendages – herpes simplex, rash, sweating, and urticaria. Special Senses – amblyopia. Urogenital – urinary tract infection.

CLINICAL PHARMACOLOGY Pharmacology The analgesic ingredient, oxycodone, is a semi-synthetic narcotic with multiple actions qualitatively similar to those of morphine; the most prominent of these involves the central nervous system and organs composed of smooth muscle. Oxycodone, as the hydrochloride salt, is a pure agonist opioid whose principal therapeutic action is analgesia and has been in clinical use since 1917. Like all pure opioid agonists, there is no ceiling effect to analgesia, such as is seen with partial agonists or non-opioid analgesics. Based upon a single dose, relative-potency study conducted in humans with cancer pain, 10 to 15 mg of oxycodone given intramuscularly produced an analgesic effect similar to 10 mg of morphine given intramuscularly. Both drugs have a 3 to 4 hour duration of action. Oxycodone retains approximately one half of its analgesic activity when administered orally. Effects on Central Nervous System – The precise mechanism of the analgesic action is unknown. However, specific CNS opioid receptors for endogenous compounds with opioid-like activity have been identified throughout the brain and spinal cord and play a role in the analgesic effects of this drug. A significant feature of opioid-induced analgesia is that it occurs without loss of consciousness. The relief of pain by morphine-like opioids is relatively selective, in that other sensory modalities, (e.g., touch, vibrations, vision, hearing, etc.) are not obtunded. Oxycodone produces respiratory depression by direct action on brain stem respiratory centers. The respiratory depression involves both a reduction in the responsiveness of the brain stem respiratory centers to increases in carbon dioxide tension and to electrical stimulation. Oxycodone depresses the cough reflex by direct effect on the cough center in the medulla. Antitussive effects may occur with doses lower than those usually required for analgesia. Oxycodone causes miosis, even in total darkness. Pinpoint pupils are a sign of opioid overdose but are not pathognomonic (e.g., pontine lesions of hemorrhagic or ischemic origins may produce similar findings). Marked mydriasis rather than miosis may be seen due to hypoxia in overdose situations. Effects on Gastrointestinal Tract and Other Smooth Muscle – Oxycodone, like other opioid analgesics, produces some degree of nausea and vomiting which is caused by direct stimulation of the chemoreceptor trigger zone (CTZ) located in the medulla. The frequency and severity of emesis gradually diminishes with time. Oxycodone may cause a decrease in the secretion of hydrochloric acid in the stomach that reduces motility while increasing the tone of the antrum, stomach, and duodenum. Digestion of food in the small intestine is delayed and propulsive contractions are decreased. Propulsive peristaltic waves in the colon are decreased, while tone may be increased to the point of spasm resulting in constipation. Other opioid-induced effects may include a reduction in biliary and pancreatic secretions, spasm of sphincter of Oddi, and transient elevations in serum amylase. Effects on Cardiovascular System – Oxycodone, in therapeutic doses, produces peripheral vasodilatation (arteriolar and venous), decreased peripheral resistance, and inhibits baroreceptor reflexes. Manifestations of histamine release and/or peripheral vasodilatation may include pruritus, flushing, red eyes, sweating, and/or orthostatic hypotension. Caution should be used in hypovolemic patients, such as those suffering acute myocardial infarction, because oxycodone may cause or further aggravate their hypotension. Caution should also be used in patients with cor pulmonale who have received therapeutic doses of opioids. Pharmacodynamics The relationship between the plasma level of oxycodone and the analgesic response will depend on the patient's age, state of health, medical condition and extent of previous opioid treatment. The minimum effective plasma concentration of oxycodone to achieve analgesia will vary widely among patients, especially among patients who have been previously treated with potent agonist opioids. Thus, patients need to be treated with individualized titration of dosage to the desired effect. The minimum effective analgesic concentration of oxycodone for any individual patient may increase with repeated dosing due to an increase in pain and/or development of tolerance. Pharmacokinetics The activity of oxycodone hydrochloride tablets is primarily due to the parent drug oxycodone. Oxycodone hydrochloride tablets are designed to provide immediate release of oxycodone. Table 1 Pharmacokinetic Parameters (Mean±SD) Dose/Parameters AUC (ng x hr/mL) Cmax (ng/mL) Tmax (hr) Cmin (ng/mL) Cavg (ng/mL) Half-Life (hr) Single Dose Pharmacokinetics Oxycodone HCl 5 mg tabs x 3 133.2±33 22.3±8.2 1.8±1.8 n/a n/a 3.73±0.9 Oxycodone HCl 15 mg tab 128.2±35.1 22.2±7.6 1.4±0.7 n/a n/a 3.55±1.0 Oxycodone HCl Liquid Concentrate 15 mg oral solution 130.6±34.7 21.1±6.1 1.9±1.5 n/a n/a 3.71±0.8 Oxycodone HCl 30 mg tab 268.2±60.7 39.3±14.0 2.6±3.0 n/a n/a 3.85±1.3 Food Effect, Single Dose Oxycodone HCl 10 mg/10 mL oral sol'n (fasted) 105±6.2 19.0±3.7 1.25±0.5 n/a n/a 2.9±0.4 Oxycodone HCl 10 mg/10 mL oral sol'n (fed) 133±25.2 17.7±3.0 2.54±1.2 n/a n/a 3.3±0.5 Multiple-Dose Studies AUC(72-84) Oxycodone HCl 5 mg tabs q6h x 14 doses 113.3±24.0 15.7±3.2 1.3±0.3 7.4±1.8 9.4±2.0 n/a Oxycodone HCl 3.33 mg (3.33 mL) oral sol'n q4h x 21 doses 99.0±24.8 12.9±3.1 1.0±0.3 7.2±2.3 9.7±2.6 n/a Absorption – About 60% to 87% of an oral dose of oxycodone reaches the systemic circulation in comparison to a parenteral dose. This high oral bioavailability (compared to other oral opioids) is due to lower pre-systemic and/or first-pass metabolism of oxycodone. The relative oral bioavailability of oxycodone hydrochloride 15 mg and 30 mg tablets, compared to the 5 mg oxycodone hydrochloride tablets, is 96% and 101% respectively. Oxycodone hydrochloride tablets 15 mg tablets and 30 mg tablets are bioequivalent to the 5 mg oxycodone hydrochloride tablets (see Table 1 Pharmacokinetic Parameters ). Dose proportionality of oxycodone has been established using the oxycodone hydrochloride tablets 5 mg tablets at doses of 5 mg, 15 mg (three 5 mg tablets) and 30 mg (six 5 mg tablets) based on extent of absorption (AUC) (see Figure 1 ). It takes approximately 18 to 24 hours to reach steady-state plasma concentrations of oxycodone with oxycodone hydrochloride tablets. Figure 1. Oxycodone Hydrochloride Dose-Proportionality Study 5 mg, 15 mg and 30 mg (single-dose) Food Effect A single-dose food effect study was conducted in normal volunteers using the 5 mg/5 mL solution. The concurrent intake of a high fat meal was shown to enhance the extent (27% increase in AUC), but not the rate of oxycodone absorption from the oral solution (see Table 1 ). In addition, food caused a delay in Tmax (1.25 to 2.54 hour). Similar effects of food are expected with the 15 mg and 30 mg tablets. Distribution – Following intravenous administration, the volume of distribution (Vss) for oxycodone was 2.6 L/kg. Plasma protein binding of oxycodone at 37°C and a pH of 7.4 was about 45%. Oxycodone has been found in breast milk (See PRECAUTIONS - Nursing Mothers ). Metabolism – Oxycodone hydrochloride is extensively metabolized to noroxycodone, oxymorphone, and their glucuronides. The major circulating metabolite is noroxycodone with an AUC ratio of 0.6 relative to that of oxycodone. Oxymorphone is present in the plasma only in low concentrations. The analgesic activity profile of other metabolites is not known at present. The formation of oxymorphone, but not noroxycodone, is mediated by CYP2D6 and as such its formation can, in theory, be affected by other drugs. (See PRECAUTIONS - Drug Interactions ). Elimination – Oxycodone and its metabolites are excreted primarily via the kidney. The amounts measured in the urine have been reported as follows: free oxycodone up to 19