2.1 General Dosing Instructions

Carefully consider the potential benefits and risks of fenoprofen calcium and other treatment options before deciding to use fenoprofen. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals. Use lowest effective dosage for the shortest duration consistent with individual patient treatment goals [see Warnings and Precautions (5)].

Fenoprofen calcium may be administered with meals or with milk. Although the total amount absorbed is not affected, peak blood levels are delayed and diminished.

Patients with rheumatoid arthritis generally seem to require larger doses of fenoprofen calcium than do those with osteoarthritis. The smallest dose that yields acceptable control should be employed.

Although improvement may be seen in a few days in many patients, an additional 2 to 3 weeks may be required to gauge the full benefits of therapy.

2.2 Analgesia

For the treatment of mild to moderate pain, the recommended dosage is 200 mg given orally every 4 to 6 hours, as needed.

2.3 Rheumatoid Arthritis and Osteoarthritis

For the relief of signs and symptoms of rheumatoid arthritis or osteoarthritis the recommended dose is 400 to 600 mg given orally, 3 or 4 times a day. The dose should be tailored to the needs of the patient and may be increased or decreased depending on the severity of the symptoms. Dosage adjustments may be made after initiation of drug therapy or during exacerbations of the disease. Total daily dosage should not exceed 3,200 mg.

5.1 Cardiovascular Thrombotic Events

Clinical trials of several COX-2 selective and nonselective NSAIDs of up to three years duration have shown an increased risk of serious cardiovascular (CV) thrombotic events, including myocardial infarction (MI) and stroke, which can be fatal. Based on available data, it is unclear that the risk for CV thrombotic events is similar for all NSAIDs. The relative increase in serious CV thrombotic events over baseline conferred by NSAID use appears to be similar in those with and without known CV disease or risk factors for CV disease. However, patients with known CV disease or risk factors had a higher absolute incidence of excess serious CV thrombotic events, due to their increased baseline rate. Some observational studies found that this increased risk of serious CV thrombotic events began as early as the first weeks of treatment. The increase in CV thrombotic risk has been observed most consistently at higher doses.

To minimize the potential risk for an adverse CV event in NSAID-treated patients, use the lowest effective dose for the shortest duration possible. Physicians and patients should remain alert for the development of such events, throughout the entire treatment course, even in the absence of previous CV symptoms. Patients should be informed about the symptoms of serious CV events and the steps to take if they occur.

There is no consistent evidence that concurrent use of aspirin mitigates the increased risk of serious CV thrombotic events associated with NSAID use. The concurrent use of aspirin and an NSAID, such as fenoprofen, increases the risk of serious gastrointestinal (GI) events [see Warnings and Precautions (5.2)].

Status Post Coronary Artery Bypass Graft (CABG) Surgery

Two large, controlled clinical trials of a COX-2 selective NSAID for the treatment of pain in the first 10 to 14 days following CABG surgery found an increased incidence of myocardial infarction and stroke. NSAIDs are contraindicated in the setting of CABG [see Contraindications (4)].

Post-MI Patients

Observational studies conducted in the Danish National Registry have demonstrated that patients treated with NSAIDs in the post-MI period were at increased risk of reinfarction, CV-related death, and all-cause mortality beginning in the first week of treatment. In this same cohort, the incidence of death in the first year post-MI was 20 per 100 person years in NSAID-treated patients compared to 12 per 100 person years in non-NSAID exposed patients. Although the absolute rate of death declined somewhat after the first year post-MI, the increased relative risk of death in NSAID users persisted over at least the next four years of follow-up.

Avoid the use of fenoprofen calcium in patients with a recent MI unless the benefits are expected to outweigh the risk of recurrent CV thrombotic events. If fenoprofen calcium is used in patients with a recent MI, monitor patients for signs of cardiac ischemia.

5.2 Gastrointestinal Bleeding, Ulceration, and Perforation

NSAIDs, including fenoprofen calcium, cause serious gastrointestinal (GI) adverse events including inflammation, bleeding, ulceration, and perforation of the esophagus, stomach, small intestine, or large intestine, which can be fatal. These serious adverse events can occur at any time, with or without warning symptoms, in patients treated with NSAIDs. Only one in five patients who develop a serious upper GI adverse event on NSAID therapy is symptomatic. Upper GI ulcers, gross bleeding, or perforation caused by NSAIDs occurred in approximately 1% of patients treated for 3-6 months, and in about 2% to 4% of patients treated for one year. However, even short-term NSAID therapy is not without risk.

Risk Factors for GI Bleeding, Ulceration, and Perforation

Patients with a prior history of peptic ulcer disease and/or GI bleeding who used NSAIDs had a greater than 10-fold increased risk for developing a GI bleed compared to patients without these risk factors. Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. Most postmarketing reports of fatal GI events occurred in elderly or debilitated patients. Additionally, patients with advanced liver disease and/or coagulopathy are at increased risk for GI bleeding.

Strategies to Minimize the GI Risks in NSAID-treated Patients:

• Use the lowest effective dosage for the shortest possible duration.
• Avoid administration of more than one NSAID at a time.
• Avoid use in patients at higher risk unless benefits are expected to outweigh the increased risk of bleeding. For such patients, as well as those with active GI bleeding, consider alternate therapies other than NSAIDs.
• Remain alert for signs and symptoms of GI ulceration and bleeding during NSAID therapy.
• If a serious GI adverse event is suspected, promptly initiate evaluation and treatment, and discontinue fenoprofen calcium until a serious GI adverse event is ruled out.
•  In the setting of concomitant use of low-dose aspirin for cardiac prophylaxis, monitor patients more closely for evidence of GI bleeding [see Drug Interactions (7)].

5.3 Hepatotoxicity

Elevations of ALT or AST (three or more times the upper limit of normal [ULN]) have been reported in approximately 1% of NSAID-treated patients in clinical trials. In addition, rare, sometimes fatal, cases of severe hepatic injury, including fulminant hepatitis, liver necrosis, and hepatic failure have been reported.

Elevations of ALT or AST (less than three times ULN) may occur in up to 15% of patients treated with NSAIDs including fenoprofen.

Inform patients of the warning signs and symptoms of hepatotoxicity (e.g., nausea, fatigue, lethargy, diarrhea, pruritus, jaundice, right upper quadrant tenderness, and “flu-like” symptoms). If clinical signs and symptoms consistent with liver disease develop, or if systemic manifestations occur (e.g., eosinophilia, rash, etc.), discontinue fenoprofen calcium immediately, and perform a clinical evaluation of the patient.

5.4 Hypertension

NSAIDs, including fenoprofen calcium, can lead to new onset of hypertension or worsening of preexisting hypertension, either of which may contribute to the increased incidence of CV events. Patients taking angiotensin converting enzyme (ACE) inhibitors, thiazide diuretics, or loop diuretics may have impaired response to these therapies when taking NSAIDs [see Drug Interactions (7)].

Monitor blood pressure (BP) during the initiation of NSAID treatment and throughout the course of therapy.

5.5 Heart Failure and Edema

The Coxib and traditional NSAID Trialists’ Collaboration meta-analysis of randomized controlled trials demonstrated an approximately two-fold increase in hospitalizations for heart failure in COX-2 selective-treated patients and nonselective NSAID-treated patients compared to placebo-treated patients. In a Danish National Registry study of patients with heart failure, NSAID use increased the risk of MI, hospitalization for heart failure, and death.

Additionally, fluid retention and edema have been observed in some patients treated with NSAIDs. Use of fenoprofen may blunt the CV effects of several therapeutic agents used to treat these medical conditions (e.g., diuretics, ACE inhibitors, or angiotensin receptor blockers [ARBs]) [see Drug Interactions (7)].

Avoid the use of fenoprofen calcium in patients with severe heart failure unless the benefits are expected to outweigh the risk of worsening heart failure. If fenoprofen calcium is used in patients with severe heart failure, monitor patients for signs of worsening heart failure.

5.6 Renal Toxicity and Hyperkalemia

Renal Toxicity

Long-term administration of NSAIDs has resulted in renal papillary necrosis and other renal injury.

Renal toxicity has also been seen in patients in whom renal prostaglandins have a compensatory role in the maintenance of renal perfusion. In these patients, administration of an NSAID may cause a dose-dependent reduction in prostaglandin formation and, secondarily, in renal blood flow, which may precipitate overt renal decompensation. Patients at greatest risk of this reaction are those with impaired renal function, dehydration, hypovolemia, heart failure, liver dysfunction, those taking diuretics and ACE inhibitors or ARBs, and the elderly. Discontinuation of NSAID therapy is usually followed by recovery to the pretreatment state.

No information is available from controlled clinical studies regarding the use of fenoprofen calcium in patients with advanced renal disease. The renal effects of fenoprofen calcium may hasten the progression of renal dysfunction in patients with preexisting renal disease.

Correct volume status in dehydrated or hypovolemic patients prior to initiating fenoprofen calcium. Monitor renal function in patients with renal or hepatic impairment, heart failure, dehydration, or hypovolemia during use of fenoprofen calcium [see Drug Interactions (7)]. Avoid the use of fenoprofen calcium in patients with advanced renal disease unless the benefits are expected to outweigh the risk of worsening renal function. If fenoprofen calcium is used in patients with advanced renal disease, monitor patients for signs of worsening renal function.

Hyperkalemia

Increases in serum potassium concentration, including hyperkalemia, have been reported with use of NSAIDs, even in some patients without renal impairment. In patients with normal renal function, these effects have been attributed to a hyporeninemic-hypoaldosteronism state.

5.7 Anaphylactic Reactions

Fenoprofen has been associated with anaphylactic reactions in patients with and without known hypersensitivity to fenoprofen and in patients with aspirin-sensitive asthma [see Contraindications (4) and Warnings and precautions (5.8)].

Seek emergency help if an anaphylactic reaction occurs.

5.8 Exacerbation of Asthma Related to Aspirin Sensitivity

A subpopulation of patients with asthma may have aspirin-sensitive asthma which may include chronic rhinosinusitis complicated by nasal polyps; severe, potentially fatal bronchospasm; and/or intolerance to aspirin and other NSAIDs. Because cross-reactivity between aspirin and other NSAIDs has been reported in such aspirin-sensitive patients, fenoprofen calcium is contraindicated in patients with this form of aspirin sensitivity [see Contraindications (4)]. When fenoprofen calcium is used in patients with preexisting asthma (without known aspirin sensitivity), monitor patients for changes in the signs and symptoms of asthma.

5.9 Serious Skin Reactions

NSAIDs, including fenoprofen, can cause serious skin adverse reactions such as exfoliative dermatitis, Stevens-Johnson Syndrome (SJS), and toxic epidermal necrolysis (TEN), which can be fatal. These serious events may occur without warning. Inform patients about the signs and symptoms of serious skin reactions, and to discontinue the use of fenoprofen calcium at the first appearance of skin rash or any other sign of hypersensitivity. Fenoprofen calcium is contraindicated in patients with previous serious skin reactions to NSAIDs [see Contraindications (4)].

5.10 Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS)

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) has been reported in patients taking NSAIDs such as fenoprofen calcium capsules. Some of these events have been fatal or life-threatening. DRESS typically, although not exclusively, presents with fever, rash, lymphadenopathy, and/or facial swelling. Other clinical manifestations may include hepatitis, nephritis, hematological abnormalities, myocarditis, or myositis. Sometimes symptoms of DRESS may resemble an acute viral infection. Eosinophilia is often present. Because this disorder is variable in its presentation, other organ systems not noted here may be involved.
It is important to note that early manifestations of hypersensitivity, such as fever or lymphadenopathy, may be present even though rash is not evident. If such signs or symptoms are present, discontinue fenoprofen calcium capsules and evaluate the patient immediately.

5.11 Fetal Toxicity

Premature Closure of Fetal Ductus Arteriosus
Avoid use of NSAIDs, including fenoprofen calcium, in pregnant women at about 30 weeks gestation and later. NSAIDs, including fenoprofen calcium, increase the risk of premature closure of the fetal ductus arteriosus at approximately this gestational age.
Oligohydramnios/Neonatal Renal Impairment
Use of NSAIDs, including fenoprofen calcium, at about 20 weeks gestation or later in pregnancy may cause fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment. These adverse outcomes are seen, on average, after days to weeks of treatment, although oligohydramnios has been infrequently reported as soon as 48 hours after NSAID initiation.
Oligohydramnios is often, but not always, reversible with treatment discontinuation. Complications of prolonged oligohydramnios may, for example, include limb contractures and delayed lung maturation. In some postmarketing cases of impaired neonatal renal function, invasive procedures such as exchange transfusion or dialysis were required.
If NSAID treatment is necessary between about 20 weeks and 30 weeks gestation, limit fenoprofen calcium use to the lowest effective dose and shortest duration possible. Consider ultrasound monitoring of amniotic fluid if fenoprofen calcium treatment extends beyond 48 hours. Discontinue fenoprofen calcium if oligohydramnios occurs and follow up according to clinical practice [see Use in Specific Populations(8.1)].

5.12 Hematologic Toxicity

Anemia has occurred in NSAID-treated patients. This may be due to occult or gross blood loss, fluid retention, or an incompletely described effect on erythropoiesis. If a patient treated with fenoprofen calcium has any signs or symptoms of anemia, monitor hemoglobin or hematocrit.

NSAIDs, including fenoprofen calcium, may increase the risk of bleeding events. Co-morbid conditions such as coagulation disorders, concomitant use of warfarin, other anticoagulants, antiplatelet agents (e.g., aspirin), serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) may increase this risk. Monitor these patients for signs of bleeding [see Drug Interactions (7)].

5.13 Masking of Inflammation and Fever

The pharmacological activity of fenoprofen calcium in reducing inflammation, and possibly fever, may diminish the utility of diagnostic signs in detecting infections.

5.14 Laboratory Monitoring

Because serious GI bleeding, hepatotoxicity, and renal injury can occur without warning symptoms or signs, consider monitoring patients on long-term NSAID treatment with a CBC and a chemistry profile periodically [see Warnings and Precautions (5.2, 5.3,5.6)].

5.15 Ocular Effects

Studies to date have not shown changes in the eyes attributable to the administration of fenoprofen calcium. However, adverse ocular effects have been observed with other anti-inflammatory drugs. Eye examinations, therefore, should be performed if visual disturbances occur in patients taking fenoprofen calcium.

5.16 Central Nervous System Effects

Caution should be exercised by patients whose activities require alertness if they experience CNS side effects while taking fenoprofen calcium.

5.17 Impact on Hearing

Since the safety of fenoprofen calcium has not been established in patients with impaired hearing, these patients should have periodic tests of auditory function during prolonged therapy with fenoprofen calcium.

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 practice.

During clinical studies for rheumatoid arthritis, osteoarthritis, or mild to moderate pain and studies of pharmacokinetics, complaints were compiled from a checklist of potential adverse reactions, and the following data emerged. These encompass observations in 6,786 patients, including 188 observed for at least 52 weeks. For comparison, data are also presented from complaints received from the 266 patients who received placebo in these same trials. During short-term studies for analgesia, the incidence of adverse reactions was markedly lower than that seen in longer-term studies.

Adverse Drug Reactions Reported in >1% of Patients During Clinical Trials

Digestive System — During clinical trials with fenoprofen calcium, the most common adverse reactions were gastrointestinal in nature and occurred in 20.8% of patients receiving fenoprofen calcium as compared to 16.9% of patients receiving placebo. In descending order of frequency, these reactions included dyspepsia (10.3% fenoprofen calcium vs. 2.3% placebo), nausea (7.7% vs. 7.1%), constipation (7% vs. 1.5%), vomiting (2.6% vs. 1.9%), abdominal pain (2% vs. 1.1%), and diarrhea (1.8% vs. 4.1%). The drug was discontinued because of adverse gastrointestinal reactions in less than 2% of patients during premarketing studies.

Nervous System — The most frequent adverse neurologic reactions were headache (8.7% vs. 7.5%) and somnolence (8.5% vs. 6.4%). Dizziness (6.5% vs. 5.6%), tremor (2.2% vs. 0.4%), and confusion (1.4% vs. none) were noted less frequently. Fenoprofen calcium was discontinued in less than 0.5% of patients because of these side effects during premarketing studies.

Skin and Appendages— Increased sweating (4.6% vs. 0.4%), pruritus (4.2% vs. 0.8%), and rash (3.7% vs. 0.4%) were reported. Fenoprofen calcium was discontinued in about 1% of patients because of an adverse effect related to the skin during premarketing studies.

Special Senses — Tinnitus (4.5% vs. 0.4%), blurred vision (2.2% vs. none), and decreased hearing (1.6% vs. none) were reported. Fenoprofen calcium was discontinued in less than 0.5% of patients because of adverse effects related to the special senses during premarketing studies.

Cardiovascular — Palpitations (2.5% vs. 0.4%). Fenoprofen calcium was discontinued in about 0.5% of patients because of adverse cardiovascular reactions during premarketing studies.

Miscellaneous — Nervousness (5.7% vs. 1.5%), asthenia (5.4% vs. 0.4%), peripheral edema (5.0% vs. 0.4%), dyspnea (2.8% vs. none), fatigue (1.7% vs. 1.5%), upper respiratory infection (1.5% vs. 5.6%), and nasopharyngitis (1.2% vs. none).

Adverse Drug Reactions Reported in <1% of Patients During Clinical Trials

Digestive System—Gastritis, peptic ulcer with/without perforation, gastrointestinal hemorrhage, anorexia, flatulence, dry mouth, and blood in the stool. Increases in alkaline phosphatase, LDH, SGOT, jaundice, and cholestatic hepatitis, aphthous ulcerations of the buccal mucosa, metallic taste, and pancreatitis.

Cardiovascular—Atrial fibrillation, pulmonary edema, electrocardiographic changes, and supraventricular tachycardia.

Genitourinary Tract—Renal failure, dysuria, cystitis, hematuria, oliguria, azotemia, anuria, interstitial nephritis, nephrosis, and papillary necrosis.

Hypersensitivity—Angioedema (angioneurotic edema).

Hematologic—Purpura, bruising, hemorrhage, thrombocytopenia, hemolytic anemia, aplastic anemia, agranulocytosis, and pancytopenia.

Nervous System—Depression, disorientation, seizures, and trigeminal neuralgia.

Special Senses—Burning tongue, diplopia, and optic neuritis.

Skin and Appendages—Exfoliative dermatitis, toxic epidermal necrolysis, Stevens-Johnson syndrome, and alopecia.

Miscellaneous—Anaphylaxis, urticaria, malaise, insomnia, tachycardia, personality change, lymphadenopathy, mastodynia, and fever.

8.1 Pregnancy

Risk Summary

Use of NSAIDs, including fenoprofen calcium, can cause premature closure of the fetal ductus arteriosus and fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment. Because of these risks, limit dose and duration of fenoprofen calcium use between about 20 and 30 weeks of gestation, and avoid fenoprofen calcium use at about 30 weeks of gestation and later in pregnancy (see Clinical Considerations, Data)

Premature Closure of Fetal Ductus Arteriosus
    Use of NSAIDs, including fenoprofen calcium, at about 30 weeks gestation or later in pregnancy increases the risk of premature closure of the fetal ductus arteriosus. 

Oligohydramnios/Neonatal Renal Impairment
    Use of NSAIDs at about 20 weeks gestation or later in pregnancy has been associated with cases of fetal renal dysfunction leading to oligohydramnios, and in some cases, neonatal renal impairment.

Data from observational studies regarding other potential embryofetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. In animal reproduction studies, embryo-fetal lethality and skeletal abnormalities were noted in offspring of pregnant rabbits following oral administration of fenoprofen during organogenesis at 0.6 times the maximum human daily dose of 3200 mg/day. However, there were no major malformations noted following oral administration of fenoprofen calcium to pregnant rats and rabbits during organogenesis at exposures up to 0.3 and 0.6 times the maximum human daily dose of 3200 mg/day.

Based on animal data, prostaglandins have been shown to have an important role in endometrial vascular permeability, blastocyst implantation, and decidualization. In animal studies, administration of prostaglandin synthesis inhibitors such as fenoprofen, resulted in increased pre- and post-implantation loss. Prostaglandins also have been shown to have an important role in fetal kidney development. In published animal studies, prostaglandin synthesis inhibitors have been reported to impair kidney development when administered at clinically relevant doses.

The estimated background risk of major birth defects and miscarriage for the indicated population(s) is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. 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.

Clinical Considerations

Fetal/Neonatal Adverse Reactions

Premature Closure of Fetal Ductus Arteriosus:
Avoid use of NSAIDs in women at about 30 weeks gestation and later in pregnancy, because NSAIDs, including fenoprofen calcium, can cause premature closure of the fetal ductus arteriosus (see Data).

Oligohydramnios/Neonatal Renal Impairment:
If an NSAID is necessary at about 20 weeks gestation or later in pregnancy, limit the use to the lowest effective dose and shortest duration possible. If fenoprofen calcium treatment extends beyond 48 hours, consider monitoring with ultrasound for oligohydramnios. If oligohydramnios occurs, discontinue fenoprofen calcium and follow up according to clinical practice (see Data).

Labor or Delivery
There are no studies on the effects of fenoprofen calcium during labor or delivery. In animal studies, NSAIDS, including fenoprofen, inhibit prostaglandin synthesis, cause delayed parturition, and increase the incidence of stillbirth.

Data
Human Data
There are no adequate and well-controlled studies of fenoprofen calcium in pregnant women. Data from observational studies regarding potential embryofetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. 

    Premature Closure of Fetal Ductus Arteriosus: 
    Published literature reports that the use of NSAIDs at about 30 weeks of gestation and later in pregnancy may cause premature closure of the fetal ductus arteriosus. 

    Oligohydramnios/Neonatal Renal Impairment: 
Published studies and postmarketing reports describe maternal NSAID use at about 20 weeks gestation or later in pregnancy associated with fetal renal dysfunction leading to oligohydramnios, and in some cases, neonatal renal impairment. These adverse outcomes are seen, on average, after days to weeks of treatment, although oligohydramnios has been infrequently reported as soon as 48 hours after NSAID initiation. In many cases, but not all, the decrease in amniotic fluid was transient and reversible with cessation of the drug. There have been a limited number of case reports of maternal NSAID use and neonatal renal dysfunction without oligohydramnios, some of which were irreversible. Some cases of neonatal renal dysfunction required treatment with invasive procedures, such as exchange transfusion or dialysis. 

Methodological limitations of these postmarketing studies and reports include lack of a control group; limited information regarding dose, duration, and timing of drug exposure; and concomitant use of other medications. These limitations preclude establishing a reliable estimate of the risk of adverse fetal and neonatal outcomes with maternal NSAID use. Because the published safety data on neonatal outcomes involved mostly preterm infants, the generalizability of certain reported risks to the full-term infant exposed to NSAIDs through maternal use is uncertain.

Animal data

Pregnant rats were treated with fenoprofen using oral doses of 50 or 100 mg/kg (0.15 times and 0.3 times the maximum human daily dose (MHDD) of 3200 mg/day based on body surface area comparison) during the period of organogenesis. No major malformations were noted and there was no evidence of maternal toxicity at these doses, however, the exposures were below the exposures that will occur in humans.

Pregnant rabbits were treated with fenoprofen using oral doses of 50 or 100 mg/kg (0.3 times and 0.6 times the MHDD of 3200 mg/day based on body surface area comparison) during the period of organogenesis. Maternal toxicity (mortality) was noted in the high dose animals. Although no major malformations were noted, there was an increased incidence of embryo-fetal lethality and skeletal abnormalities were present at 0.6 times the MHDD.

Pregnant rats were treated from Gestation Day 14 through Post-Natal Day 20 with oral doses of fenoprofen of 6.25, 12.5, 25, 50, or 100 mg/kg (0.02, 0.04, 0.08, 0.15, or 0.3 times the MDD of 3200 mg/day based on body surface area comparison). All doses produced significant toxicity, including vaginal bleeding, prolonged parturition, increased stillbirths, and maternal deaths.

Pregnant rats were treated from Gestation Day 6 through Gestation Day 19 and Post Partum Day 1 to 20 (excluding parturition) with an oral dose of fenoprofen of 100 mg/kg (0.3 times the MDD of 3200 mg/day based on body surface area comparison) demonstrated only a small increase in the incidence of impaired parturition despite the presence of maternal toxicity (gastrointestinal ulceration and renal toxicity).

8.2 Lactation

Risk Summary

In a published study, after a dose of 600 mg every 6 hours for 4 days in postpartum mothers, breastmilk fenoprofen calcium levels were reportedly 1.6% of those in maternal plasma.  Because there is little published experience with fenoprofen during breastfeeding, other agents may be preferred, especially while nursing a newborn or preterm infant. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for fenoprofen calcium and any potential adverse effects on the breastfed infant from the fenoprofen or from the underlying maternal condition.

8.3 Females and Males of Reproductive Potential

Infertility

Females

Based on the mechanism of action, the use of prostaglandin-mediated NSAIDs, including fenoprofen calcium, may delay or prevent rupture of ovarian follicles, which has been associated with reversible infertility in some women. Published animal studies have shown that administration of prostaglandin synthesis inhibitors has the potential to disrupt prostaglandin-mediated follicular rupture required for ovulation. Small studies in women treated with NSAIDs have also shown a reversible delay in ovulation. Consider withdrawal of NSAIDs, including fenoprofen calcium, in women who have difficulties conceiving or who are undergoing investigation of infertility.

8.4 Pediatric Use

Safety and effectiveness in pediatric patients under the age of 18 have not been established.

8.5 Geriatric Use

Elderly patients, compared to younger patients, are at greater risk for NSAID-associated serious cardiovascular, gastrointestinal, and/or renal adverse reactions. If the anticipated benefit for the elderly patient outweighs these potential risks, start dosing at the low end of the dosing range, and monitor patients for adverse effects [see Warnings and Precautions (5.1,5.2, 5.3,5.6, 5.14)].

12.1 Mechanism of Action

Fenoprofen has analgesic, anti-inflammatory, and antipyretic properties.

The mechanism of action of fenoprofen calcium, like that of other NSAIDs, is not completely understood but involves inhibition of cyclooxygenase (COX-1 and COX-2).

Fenoprofen is a potent inhibitor of prostaglandin synthesis in vitro. Fenoprofen concentrations reached during therapy have produced in vivo effects. Prostaglandins sensitize afferent nerves and potentiate the action of bradykinin in inducing pain in animal models. Prostaglandins are mediators of inflammation. Because fenoprofen is an inhibitor of prostaglandin synthesis, its mode of action may be due to a decrease of prostaglandins in peripheral tissues.

12.3 Pharmacokinetics

Absorption

Under fasting conditions, fenoprofen is rapidly absorbed, and peak plasma levels of 50 mcg/L are achieved within 2 hours after oral administration of 600 mg doses. Good dose proportionality was observed between 200 and 600 mg doses in fasting male volunteers.

Distribution

Fenoprofen is highly bound (99%) to albumin.

Elimination

Metabolism

The plasma half-life is approximately 3 hours.

Excretion

About 90% of a single oral dose is eliminated within 24 hours as fenoprofen glucuronide and 4'-hydroxyfenoprofen glucuronide, the major urinary metabolites of fenoprofen.

Specific Populations

Geriatrics

Peak plasma levels of fenoprofen in normal elderly volunteers were similar to those observed in normal young volunteers. Elderly volunteers had a mean plasma clearance of 2.2 L/hour while plasma clearance of fenoprofen in normal young volunteers ranged from 3 to 3.5 L/hour. The overall elimination rate constant, plasma half-life and ratio of renal to nonrenal clearance of fenoprofen was the same in elderly and young volunteers. The 30 to 60% decrease in plasma clearance is due to a decrease in the volume of distribution in the body.

Drug Interaction Studies

Aspirin: When NSAIDs were administered with aspirin, the protein binding of NSAIDs were reduced, although the clearance of free NSAID was not altered. The clinical significance of this interaction is not known. See Table 1 for clinically significant drug interactions of NSAIDs with aspirin [see Drug Interactions (7)].

Antacid: The concomitant administration of antacid (containing both aluminum and magnesium hydroxide) does not interfere with absorption of fenoprofen.

13.1 Carcinogenesis, Mutagenesis, and Impairment of Fertility

Carcinogenesis

Long-term studies in animals to evaluate the carcinogenic potential of fenoprofen have not been conducted.

Mutagenesis

Studies to evaluate the genotoxic potential of fenoprofen have not been conducted.

Impairment of Fertility

Female and Male rats were treated with 60 to 70 mg/kg/day or 120 to 150 mg/kg/day fenoprofen calcium via the diet (approximately 0.2 or 0.4 times the maximum human daily dose of 3200 mg/day based on body surface area comparison, respectively). Male rats were treated from 77 days prior to mating and during mating. Female rats were treated from 14 days prior to mating and through gestation. Pregnancy rates were slightly reduced in the low and high dose groups compared to controls. There was no adverse effect on implantations, resorptions, or live fetuses.