NALFON Capsule Ref.[10055] Active ingredients: Fenoprofen

Source: FDA, National Drug Code (US)  Revision Year: 2020 

4. Contraindications

NALFON is contraindicated in the following patients:

  • Known hypersensitivity (e.g., anaphylactic reactions and serious skin reactions) to fenoprofen or any components of the drug product [see Warnings and Precautions (5.7, 5.9)]
  • History of asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDs. Severe, sometimes fatal, anaphylactic reactions to NSAIDs have been reported in such patients [see Warnings and Precautions (5.7, 5.8)]
  • In the setting of coronary artery bypass graft (CABG) surgery [see Warnings and Precautions (5.1)]

5. Warnings and Precautions

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 10–14 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 NALFON in patients with a recent MI unless the benefits are expected to outweigh the risk of recurrent CV thrombotic events. If NALFON is used in patients with a recent MI, monitor patients for signs of cardiac ischemia.

5.2 Gastrointestinal Bleeding, Ulceration, and Perforation

NSAIDs, including NALFON, 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%-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 of developing a GI bleed compared to patients without these risk factors. Other factors that increase the risk for 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 theincreased risk of bleeding. For such patients, as well as those with active GIbleeding, 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 NALFON 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 NALFON immediately, and perform a clinical evaluation of the patient.

5.4 Hypertension

NSAIDs, including NALFON, can lead to new onset of hypertension or worsening of pre-existing 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 NALFON in patients with severe heart failure unless the benefits are expected to outweigh the risk of worsening heart failure. If NALFON 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 NALFON in patients with advanced renal disease. The renal effects of NALFON may hasten the progression of renal dysfunction in patients with pre-existing renal disease.

Correct volume status in dehydrated or hypovolemic patients prior to initiating NALFON. Monitor renal function in patients with renal or hepatic impairment, heart failure, dehydration, or hypovolemia during use of NALFON [see Drug Interactions (7)]. Avoid the use of NALFON in patients with advanced renal disease unless the benefits are expected to outweigh the risk of worsening renal function. If NALFON 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, NALFON is contraindicated in patients with this form of aspirin sensitivity [see Contraindications (4)]. When NALFON 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 fenopropfen, 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 NALFON at the first appearance of skin rash or any other sign of hypersensitivity.

NALFON is contraindicated in patients with previous serious skin reactions to NSAIDs [see Contraindications (4)].

5.10 Premature Closure of Fetal Ductus Arteriosus

Fenoprofen may cause premature closure of the fetal ductus arteriosus. Avoid use of NSAIDs, including NALFON, in pregnant women starting at 30 weeks of gestation (third trimester) [see Use in Specific Populations (8.1)].

5.11 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 NALFON has any signs or symptoms of anemia, monitor hemoglobin or hematocrit.

NSAIDs, including NALFON, 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)].

5.12 Masking of Inflammation and Fever

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

5.13 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)].

5.14 Ocular Effects

Studies to date have not shown changes in the eyes attributable to the administration of NALFON. 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 NALFON.

5.15 Central Nervous System Effects

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

5.16 Impact on Hearing

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

6. Adverse Reactions

The following adverse reactions are discussed in greater detail in other sections of the labeling:

  • Cardiovascular Thrombotic Events [see Warnings and Precautions (5.1)]
  • GI Bleeding, Ulceration and Perforation [see Warnings and Precautions (5.2)]
  • Hepatotoxicity [see Warnings and Precautions (5.3)]
  • Hypertension [see Warnings and Precautions (5.4)]
  • Heart Failure and Edema [see Warnings and Precautions (5.5)]
  • Renal Toxicity and Hyperkalemia [see Warnings and Precautions (5.6)]
  • Anaphylactic Reactions [see Warnings and Precautions (5.7)]
  • Serious Skin Reactions [see Warnings and Precautions (5.9)]
  • Hematologic Toxicity [see Warnings and Precautions (5.11)]

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 Nalfon, the most common adverse reactions were gastrointestinal in nature and occurred in 20.8% of patients receiving Nalfon as compared to 16.9% of patients receiving placebo. In descending order of frequency, these reactions included dyspepsia (10.3% Nalfon 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. Nalfon 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. Nalfon 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. Nalfon 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%). Nalfon 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.

7. Drug Interactions

See Table 1 for clinically significant drug interactions with fenoprophen.

Table 1. Clinically Significant Drug Interactions with Fenoprofen:

Drugs That Interfere with Hemostasis
Clinical Impact: • Fenoprofen and anticoagulants such as warfarin have a synergistic effect on bleeding. The concomitant use of fenoprofen and anticoagulants have an increased risk of serious bleeding compared to the use of either drug alone.
• Serotonin release by platelets plays an important role in hemostasis. Case-control and cohort epidemiological studies showed that concomitant use of drugs that interfere with serotonin reuptake and an NSAID may potentiate the risk of bleeding more than an NSAID alone.
Intervention: Monitor patients with concomitant use of NALFON with anticoagulants (e.g., warfarin), antiplatelet agents (e.g., aspirin), selective serotonin reuptake inhibitors (SSRIs), and serotonin norepinephrine reuptake inhibitors (SNRIs) for signs of bleeding [see Warnings and Precautions (5.11)].
Aspirin
Clinical Impact: Controlled clinical studies showed that the concomitant use of NSAIDs and analgesic doses of aspirin does not produce any greater therapeutic effect than the use of NSAIDs alone. In a clinical study, the concomitant use of an NSAID and aspirin was associated with a significantly increased incidence of GI adverse reactions as compared to use of the NSAID alone [see Warnings and Precautions (5.2)].
Intervention: Concomitant use of NALFON and analgesic doses of aspirin is not generally recommended because of the increased risk of bleeding [see Warnings and Precautions (5.11)]. NALFON is not a substitute for low dose aspirin for cardiovascular protection.
ACE Inhibitors, Angiotensin Receptor Blockers, and Beta-Blockers
Clinical Impact: • NSAIDs may diminish the antihypertensive effect of angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), or beta-blockers (including propranolol).
• In patients who are elderly, volume-depleted (including those on diuretic therapy), or have renal impairment, co-administration of an NSAID with ACE inhibitors or ARBs may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible.
Intervention: • During concomitant use of NALFON and ACE-inhibitors, ARBs, or betablockers, monitor blood pressure to ensure that the desired blood pressure is obtained.
• During concomitant use of NALFON ACE-inhibitors or ARBs in patients who are elderly, volume-depleted, or have impaired renal function, monitor for signs of worsening renal function [see Warnings and Precautions (5.6)].
• When these drugs are administered concomitantly, patients should be adequately hydrated. Assess renal function at the beginning of the concomitant treatment and periodically thereafter.
Diuretics
Clinical Impact: Clinical studies, as well as post-marketing observations, showed that NSAIDs reduced the natriuretic effect of loop diuretics (e.g., furosemide) and thiazide diuretics in some patients. This effect has been attributed to the NSAID inhibition of renal prostaglandin synthesis.
Intervention: During concomitant use of NALFON with diuretics, observe patients for signs of worsening renal function, in addition to assuring diuretic efficacy including antihypertensive effects [see Warnings and Precautions (5.6)].
Digoxin
Clinical Impact: The concomitant use of fenoprofen with digoxin has been reported to increase the serum concentration and prolong the half-life of digoxin.
Intervention: During concomitant use of NALFON and digoxin, monitor serum digoxin levels.
Lithium
Clinical Impact: NSAIDs have produced elevations in plasma lithium levels and reductions in renal lithium clearance. The mean minimum lithium concentration increased 15%, and the renal clearance decreased by approximately 20%. This effect has been attributed to NSAID inhibition of renal prostaglandin synthesis.
Intervention: During concomitant use of NALFON and lithium, monitor patients for signs of lithium toxicity.
Methotrexate
Clinical Impact: Concomitant use of NSAIDs and methotrexate may increase the risk for methotrexate toxicity (e.g., neutropenia, thrombocytopenia, renal dysfunction).
Intervention: During concomitant use of NALFON and methotrexate, monitor patients for methotrexate toxicity.
Cyclosporine
Clinical Impact: Concomitant use of NALFON and cyclosporine may increase cyclosporine’s nephrotoxicity.
Intervention: During concomitant use of NALFON and cyclosporine, monitor patients for signs of worsening renal function.
NSAIDs and Salicylates
Clinical Impact: Concomitant use of fenoprofen with other NSAIDs or salicylates (e.g., diflunisal, salsalate) increases the risk of GI toxicity, with little or no increase in efficacy [see Warnings and Precautions (5.2)].
Intervention: The concomitant use of fenoprofen with other NSAIDs or salicylates is not recommended.
Pemetrexed
Clinical Impact: Concomitant use of NALFON and pemetrexed may increase the risk of pemetrexed-associated myelosuppression, renal, and GI toxicity (see the pemetrexed prescribing information).
Intervention: During concomitant use of NALFON and pemetrexed, in patients with renal impairment whose creatinine clearance ranges from 45 to 79 mL/min, monitor for myelosuppression, renal and GI toxicity.NSAIDs with short elimination half-lives (e.g., diclofenac, indomethacin) should be avoided for a period of two days before, the day of, and two days following administration of pemetrexed.In the absence of data regarding potential interaction between pemetrexed and NSAIDs with longer half-lives (e.g., meloxicam, nabumetone), patients taking these NSAIDs should interrupt dosing for at least five days before, the day of, and two days following pemetrexed administration.
Phenobarbital
Clinical Impact: Chronic administration of phenobarbital, a known enzyme inducer, may be associated with a decrease in the plasma half-life of fenoprofen.
Intervention: When phenobarbital is added to or withdrawn from treatment, dosage adjustment of NALFON may be required.
Hydantoins, sulfonamides, or sulfonylureas
Clinical Impact: In vitro studies have shown that fenoprofen, because of its affinity for albumin, may displace from their binding sites other drugs that are also albumin bound, and this may lead to drug interactions. Theoretically, fenoprofen could likewise be displaced.
Intervention: Patients receiving hydantoins, sulfonamides, or sulfonylureas should be observed for increased activity of these drugs and, therefore, signs of toxicity from these drugs.

Drug/Laboratory Test Interactions

Amerlex-M kit assay values of total and free triiodothyronine in patients receiving Nalfon have been reported as falsely elevated on the basis of a chemical cross-reaction that directly interferes with the assay. Thyroid-stimulating hormone, total thyroxine, and thyrotropin-releasing hormone response are not affected. Thus, results of the Amerlex-M kit assay should be interpreted with caution in these patients.

8.1. Pregnancy

Risk Summary

Use of NSAIDs, including NALFON, during the third trimester of pregnancy increases the risk of premature closure of the fetal ductus arteriosus. Avoid use of NSAIDs, including NALFON, in pregnant women starting at 30 weeks of gestation (third trimester).

There are no adequate and well-controlled studies of NALFON 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. In the general U.S. population, all clinically recognized pregnancies, regardless of drug exposure, have a background rate of 2-4% for major malformations, and 15-20% for pregnancy loss.

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.

Clinical Considerations

Labor or Delivery

There are no studies on the effects of NALFON 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 NALFON 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.

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 levels were reportedly 1.6% of those in maternal plasma. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for NALFON and any potential adverse effects on the breastfed infant from the NALFON 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 NALFON, 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 prostaglandinmediated 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 NALFON, 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, 5.13)].

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