Monday, October 3, 2016

Cyclosporine Injection




Cyclosporine Injection USP

Rx ONLY


FOR INFUSION ONLY




WARNING


Only physicians experienced in immunosuppressive therapy and management of organ transplant patients should prescribe cyclosporine. Patients receiving the drug should be managed in facilities equipped and staffed with adequate laboratory and supportive medical resources. The physician responsible for maintenance therapy should have complete information requisite for the follow-up of the patient.


Cyclosporine should be administered with adrenal corticosteroids but not with other immunosuppressive agents. Increased susceptibility to infection and the possible development of lymphoma may result from immunosuppression.



Cyclosporine Injection Description

Cyclosporine is a cyclic polypeptide immunosuppressant agent consisting of 11 amino acids. It is produced as a metabolite by the fungus species Fusarium solari. Chemically, cyclosporine is designated as [R - [R*,R* - (E)]] - Cyclic(L - alanyl - D - alanyl - N - methyl - L - leucyl - N - methyl - L - leucyl - N - methyl - L - valyl - 3 - hydroxy - N,4 - dimethyl - L - 2 - amino - 6 - octenoyl - L - α - aminobutyryl - N - methylglycyl - N - methyl - L - leucyl - L - valyl - N - methyl - L - leucyl).


Each mL contains cyclosporine, USP 50 mg; polyoxyethylated castor oil 650 mg; absolute alcohol 33.2% (v/v) and water for injection, q.s. Cyclosporine Injection, USP is for intravenous infusion only and must be diluted further with 0.9% Sodium Chloride Injection or 5% Dextrose Injection before use.


The structural formula is as follows:



Molecular Formula: C62H111N11O12


M.W. =1202.64



Cyclosporine Injection - Clinical Pharmacology


Cyclosporine is a potent immunosuppressive agent which in animals prolongs survival of allogeneic transplants involving skin, heart, kidney, pancreas, bone marrow, small intestine, and lung. Cyclosporine has been demonstrated to suppress some humoral immunity and to a greater extent, cell-mediated reactions such as allograft rejection, delayed hypersensitivity, experimental allergic encephalomyelitis, Freund’s adjuvant arthritis, and graft vs. host disease in many animal species for a variety of organs.


Successful kidney, liver, and heart allogeneic transplants have been performed in man using cyclosporine.


The exact mechanism of action of cyclosporine is not known. Experimental evidence suggests that the effectiveness of cyclosporine is due to specific and reversible inhibition of immunocompetent lymphocytes in the G0- or G1-phase of the cell cycle. T-lymphocytes are preferentially inhibited. The T-helper cell is the main target, although the T-suppressor cell may also be suppressed. Cyclosporine also inhibits lymphokine production and release including interleukin-2 or T-cell growth factor (TCGF).


No functional effects on phagocytic (changes in enzyme secretions not altered, chemotactic migration of granulocytes, macrophage migration, carbon clearance in vivo) or tumor cells (growth rate, metastasis) can be detected in animals. Cyclosporine does not cause bone marrow suppression in animal models or man.


The absorption of cyclosporine from the gastrointestinal tract is incomplete and variable. Peak concentrations (Cmax) in blood and plasma are achieved at about 3.5 hours. Cmax and area under the plasma or blood concentration/time curve (AUC) increase with the administered dose; for blood, the relationship is curvilinear (parabolic) between 0 and 1400 mg. As determined by a specific assay, Cmax is approximately 1 ng/mL/mg of dose for plasma and 2.7 to 1.4 ng/mL/mg of dose for blood (for low to high doses).


Cyclosporine is distributed largely outside the blood volume. In blood the distribution is concentration dependent. Approximately 33% to 47% is in plasma, 4% to 9% in lymphocytes, 5% to 12% in granulocytes, and 41% to 58% in erythrocytes. At high concentrations, the uptake by leukocytes and erythrocytes becomes saturated. In plasma, approximately 90% is bound to proteins, primarily lipoproteins.


The disposition of cyclosporine from blood is biphasic with a terminal half-life of approximately 19 hours (range: 10 to 27 hours). Elimination is primarily biliary with only 6% of the dose excreted in the urine.


Cyclosporine is extensively metabolized but there is no major metabolic pathway. Only 0.1% of the dose is excreted in the urine as unchanged drug. Of 15 metabolites characterized in human urine, 9 have been assigned structures. The major pathways consist of hydroxylation of the Cγ-carbon of 2 of the leucine residues, Cη-carbon hydroxylation, and cyclic ether formation (with oxidation of the double bond) in the side chain of the amino acid 3-hydroxyl-N,4-dimethyl-L-2-amino-6-octenoic acid and N-demethylation of N-methyl leucine residues. Hydrolysis of the cyclic peptide chain or conjugation of the aforementioned metabolites do not appear to be important biotransformation pathways.



Indications and Usage for Cyclosporine Injection


Cyclosporine is indicated for the prophylaxis of organ rejection in kidney, liver, and heart allogeneic transplants. It is always to be used with adrenal corticosteroids. The drug may also be used in the treatment of chronic rejection in patients previously treated with other immunosuppressive agents.


Because of the risk of anaphylaxis, Cyclosporine Injection should be reserved for patients who are unable to take the soft gelatin capsules or oral solution.



Contraindications


Cyclosporine is contraindicated in patients with a hypersensitivity to cyclosporine and/or polyoxyethylated castor oil.



Warnings


(See boxed WARNING.)


Cyclosporine, when used in high doses, can cause hepatotoxicity and nephrotoxicity.


It is not unusual for serum creatinine and BUN levels to be elevated during cyclosporine therapy. These elevations in renal transplant patients do not necessarily indicate rejection, and each patient must be fully evaluated before dosage adjustment is initiated.


Nephrotoxicity has been noted in 25% of cases of renal transplantation, 38% of cases of cardiac transplantation, and 37% of cases of liver transplantation. Mild nephrotoxicity was generally noted 2 to 3 months after transplant and consisted of an arrest in the fall of the preoperative elevations of BUN and creatinine at a range of 35 to 45 mg/dL and 2 to 2.5 mg/dL respectively. These elevations were often responsive to dosage reduction.


More overt nephrotoxicity was seen early after transplantation and was characterized by a rapidly rising BUN and creatinine. Since these events are similar to rejection episodes, care must be taken to differentiate between them. This form of nephrotoxicity is usually responsive to cyclosporine dosage reduction.


Although specific diagnostic criteria which reliably differentiate renal graft rejection from drug toxicity have not been found, a number of parameters have been significantly associated to one or the other. It should be noted, however, that up to 20% of patients may have simultaneous nephrotoxicity and rejection.








































Nephrotoxicity vs Rejection
ParameterNephrotoxicityRejection
History

Donor > 50 years old or hypotensive


Prolonged kidney preservation


Prolonged anastomosis time


Concomitant nephrotoxic drugs



Antidonor immune response


Retransplant patient


Clinical

Often > 6 weeks postopb


Prolonged initial nonfunction (acute tubular necrosis



Often < 4 weeks postopb


Fever > 37.5°C


Weight gain > 0.5 kg


Graft swelling and tenderness


Decrease in daily urine volume > 500 mL (or 50%)


Laboratory

CyA serum trough level > 200 ng/mL


Gradual rise in Cr (<0.15 mg/dL/day)a


Cr plateau < 25% above baseline Cr > 25% above baselinea


BUN/Cr ≥ 20



CyA serum trough level < 150 ng/mL


Rapid rise in Cr (> 0.3 mg/dL/day)a


BUN/Cr < 20


Biopsy

Arteriolopathy (medial hypertrophya, hyalinosis, nodular deposits, intimal thickening, endothelial vacuolization, progressive scarring)


Tubular atrophy, isometric vacuolization, isolated calcifications


Minimal edema


Mild focal infiltratesc


Diffuse interstitial fibrosis, often striped form



Endovasculitisc (proliferationa, intimal arteritisb, necrosis, sclerosis)


Tubulitis with RBCb and WBCb casts, some irregular vacuolization


Interstital edemac and hemorrhageb


Diffuse moderate to severe mononuclear infiltratesd


Glomerulitis (mononuclear cells)c
Aspiration Cytology

CyA deposits in tubular and endothelial cells


Fine isometric vacuolization of tubular cells



Inflammatory infiltrate with mononuclear phagocytes, macrophages, lymphoblastoid cells, and activated T-cells


These strongly express HLA-DR antigens
Urine CytologyTubular cells with vacuolization and granularizationDegenerative tubular cells, plasma cells, and lymphocyturia > 20% of sediment
ManometryIntracapsular pressure < 40 mm HgbIntracapsular pressure > 40 mm Hgb
UltrasonographyUnchanged graft cross-sectional areaIncrease in graft cross-sectional areaAP diameter ≥ Transverse diameter
Magnetic Resonance ImageryNormal appearanceLoss of distinct corticomedullary junction, swelling, image intensity of parachyma approaching that of psoas, loss of hilar fat
Radionuclide Scan

Normal or generally decreased perfusion


Decrease in tubular function


(131I-hippuran) > decrease in perfusion


(99mTc DTPA)



Patchy arterial flow


Decrease in perfusion > decrease in tubular function


Increased uptake of Indium 111 labeled platelets or Tc-99m in colloid


TherapyResponds to decreased cyclosporineResponds to increased steroids or antilymphocyte globulin

ap< 0.05, bp < 0.01, cp <0.001, dp<0.0001


A form of chronic progressive cyclosporine-associated nephrotoxicity is characterized by serial deterioration in renal function and morphologic changes in the kidneys. From 5% to 15% of transplant recipients will fail to show a reduction in a rising serum creatinine despite a decrease or discontinuation of cyclosporine therapy. Renal biopsies from these patients will demonstrate an interstitial fibrosis with tubular atrophy. In addition, toxic tubulopathy, peritubular capillary congestion, arteriolopathy, and a striped form of interstitial fibrosis with tubular atrophy may be present. Though none of these morphologic changes is entirely specific, a histologic diagnosis of chronic progressive cyclosporine-associated nephrotoxicity requires evidence of these.


When considering the development of chronic nephrotoxicity it is noteworthy that several authors have reported an association between the appearance of interstitial fibrosis and higher cumulative doses or persistently high circulating trough levels of cyclosporine. This is particularly true during the first 6 posttransplant months when the dosage tends to be highest and when, in kidney recipients, the organ appears to be most vulnerable to the toxic effects of cyclosporine. Among other contributing factors to the development of interstitial fibrosis in these patients must be included, prolonged perfusion time, warm ischemia time, as well as episodes of acute toxicity, and acute and chronic rejection. The reversibility of interstitial fibrosis and its correlation to renal function have not yet been determined.


Impaired renal function at any time requires close monitoring, and frequent dosage adjustment may be indicated. In patients with persistent high elevations of BUN and creatinine who are unresponsive to dosage adjustments, consideration should be given to switching to other immunosuppressive therapy. In the event of severe and unremitting rejection, it is preferable to allow the kidney transplant to be rejected and removed rather than increase the cyclosporine dosage to a very high level in an attempt to reverse the rejection.


Occasionally patients have developed a syndrome of thrombocytopenia and microangiopathic hemolytic anemia which may result in graft failure. The vasculopathy can occur in the absence of rejection and is accompanied by avid platelet consumption within the graft as demonstrated by Indium 111 labeled platelet studies. Neither the pathogenesis nor the management of this syndrome is clear. Though resolution has occurred after reduction or discontinuation of cyclosporine and 1) administration of streptokinase and heparin or 2) plasmapheresis, this appears to depend upon early detection with Indium 111 labeled platelet scans. (See ADVERSE REACTIONS.)


Significant hyperkalemia (sometimes associated with hyperchloremic metabolic acidosis) and hyperuricemia have been seen occasionally in individual patients.


Hepatotoxicity has been noted in 4% of cases of renal transplantation, 7% of cases of cardiac transplantation, and 4% of cases of liver transplantation. This was usually noted during the first month of therapy when high doses of cyclosporine were used and consisted of elevations of hepatic enzymes and bilirubin. The chemistry elevations usually decreased with a reduction in dosage.


As in patients receiving other immunosuppressants, those patients receiving cyclosporine are at increased risk for development of lymphomas and other malignancies, particularly those of the skin. The increased risk appears related to the intensity and duration of immunosuppression rather than to the use of specific agents. Because of the danger of oversuppression of the immune system, which can also increase susceptibility to infection, cyclosporine should not be administered with other immunosuppressive agents except adrenal corticosteroids. The efficacy and safety of cyclosporine in combination with other immunosuppressive agents have not been determined. Some malignancies may be fatal. Transplant patients receiving cyclosporine are at increased risk for serious infection with fatal outcome.


Latent Viral Infections


Immunosuppressed patients are at increased risk for opportunistic infections, including activation of latent viral infections. These include BK virus-associated nephropathy which has been observed in patients receiving immunosuppressants, including cyclosporine. This infection is associated with serious outcomes, including deteriorating renal function and renal graft loss. Patient monitoring may help detect patients at risk for BK virus-associated nephropathy. Reduction in immunosuppression should be considered for patients who develop evidence of BK virus-associated nephropathy.


There have been reports of convulsions in adult and pediatric patients receiving cyclosporine, particularly in combination with high dose methylprednisolone.


Encephalopathy has been described both in post-marketing reports and in the literature. Manifestations include impaired consciousness, convulsions, visual disturbances (including blindness), loss of motor function, movement disorders and psychiatric disturbances. In many cases, changes in the white matter have been detected using imaging techniques and pathologic specimens. Predisposing factors such as hypertension, hypomagnesemia, hypocholesterolemia, highdose corticosteriods, high cyclosporine blood concentrations, and graft-versus-host disease have been noted in many but not all of the reported cases. The changes in most cases have been reversible upon discontinuation of cyclosporine, and in some cases, improvement was noted after reduction of dose. It appears that patients receiving liver transplant are more susceptible to encephalopathy than those patients receiving kidney transplant. Another rare manifestation of cyclosporine-induced neurotoxicity is optic disc edema including papilloedema, with possible visual impairment, secondary to benign intracranial hypertension.


Rarely (approximately 1 in 1000), patients receiving Cyclosporine Injection have experienced anaphylactic reactions. Although the exact cause of these reactions is unknown, it is believed to be due to the polyoxyethylated castor oil used as the vehicle for the I.V. formulation. These reactions can consist of flushing of the face and upper thorax, and non-cardiogenic pulmonary edema, with acute repiratory distress, dyspnea, wheezing, blood pressure changes, and tachycardia. One patient died after respiratory arrest and aspiration pneumonia. In some cases, the reaction subsided after the infusion was stopped.


Patients receiving Cyclosporine Injection should be under continuous observation for at least the first 30 minutes following the start of the infusion and at frequent intervals thereafter. If anaphylaxis occurs, the infusion should be stopped. An aqueous solution of epinephrine 1:1000 should be available at the bedside as well as a source of oxygen.


Anaphylactic reactions have not been reported with the soft gelatin capsules or oral solution which lack polyoxyethylated castor oil. In fact, patients experiencing anaphylactic reactions have been treated subsequently with the soft gelatin capsules or oral solution without incident.


Care should be taken in using cyclosporine with nephrotoxic drugs. (See PRECAUTIONS.)


Because Cyclosporine Injection is not bioequivalent to Neoral®, conversion from Neoral® to Cyclosporine Injection using a 1:1 ratio (mg/kg/day) may result in a lower cyclosporine blood concentration. Conversion from Neoral® to Cyclosporine Injection should be made with increased blood concentration monitoring to avoid the potential of underdosing.



Precautions



General


Hypertension is a common side effect of cyclosporine therapy. (See ADVERSE REACTIONS.) Mild or moderate hypertension is more frequently encountered than severe hypertension and the incidence decreases over time. Antihypertensive therapy may be required. Control of blood pressure can be accomplished with any of the common antihypertensive agents. However, since cyclosporine may cause hyperkalemia, potassium-sparing diuretics should not be used. While calcium antagonists can be effective agents in treating cyclosporine-associated hypertension, care should be taken since interference with cyclosporine metabolism may require a dosage adjustment. (See Drug interactions.)


During treatment with cyclosporine, vaccination may be less effective and the use of live attenuated vaccines should be avoided.



Information for patients


Patients should be advised that any change of cyclosporine formulation should be made cautiously and only under physician supervision because it may result in the need for a change in dosage.


Patients should be informed of the necessity of repeated laboratory tests while they are receiving the drug. They should be given careful dosage instructions, advised of the potential risks during pregnancy, and informed of the increased risk of neoplasia.



Laboratory tests


Renal and liver functions should be assessed repeatedly by measurement of BUN, serum creatinine, serum bilirubin, and liver enzymes.



Interactions


Drug interactions

All of the individual drugs cited below are well substantiated to interact with cyclosporine. In addition, concomitant non-steroidal anti-inflammatory drugs, particularly in the setting of dehydration, may potentiate renal dysfunction.



Drugs That May Potentiate Renal Dysfunction

















Antibioticsciprofloxacin, gentamicin, tobramycin, vancomycin, trimethoprim with sulfamethoxazole
Antineoplasticsmelphalan
Antifungalsamphotericin B, ketoconazole
Anti-Inflammatory Drugsazapropazon, colchicine, diclofenac, naproxen, sulindac
Gastrointestinal Agentscimetidine, ranitidine
Immunosuppressivestacrolimus
Other Drugsfibric acid derivatives (e.g., bezafibrate, fenofibrate)

Drugs That Alter Cyclosporine Concentrations:

Cyclosporine is extensively metabolized by CYP 3A isoenzymes, in particular CYP3A4, and is a substrate of the multidrug efflux transporter P-glycoprotein. Various agents are known to either increase or decrease plasma or whole blood of cyclosporine levels usually by inhibition or induction of CYP3A4 or P-glycoprotein transporter or both.


Compounds that decrease cyclosporine absorption such as orlistat should be avoided. Cyclosporine is extensively metabolized by cytochrome P-450 3A. Monitoring of circulating cyclosporine concentrations and appropriate cyclosporine dosage adjustment are essential when these drugs are used concomitantly. (See Blood Level Monitoring.)



Drugs That Increase Cyclosporine Concentrations













Antibioticsazithromycin, clarithromycin, erythromycin, quinupristin/dalfopristin
Antifungalsfluconazole, itraconazole, ketoconazole, voriconazole
Calcium Channel Blockersdiltiazem, nicardipine, verapamil
Glucocorticoidsmethylprednisolone
Other Drugsallopurinol, amiodarone, bromocriptine, colchicine, danazol, metoclopromide, imatinib, nefazodone, oral contraceptives

The HIV protease inhibitors (e.g., indinavir, nelfinavir, ritonavir, and saquinavir) are known to inhibit cytochrome P-450 3A and thus could potentially increase the concentrations of cyclosporine; however, no formal studies of the interaction are available. Care should be exercised when these drugs are administered concomitantly.


Grapefruit and grapefruit juice affect metabolism, increasing blood concentrations of cyclosporine, thus should be avoided.



Drugs/Dietary Supplements That Decrease Cyclosporine Concentrations









Antibioticsnafcillin, rifampin
Anticonvulsantscarbamazepine, oxcarbazepine, phenobarbital, phenytoin
Other Drugs/Dietary Supplementsbosentan, octreotide, orlistat, sulfinpyrazone, terbinafine, ticlopidine, St. John’s Wort

There have been reports of a serious drug interaction between cyclosporine and the herbal dietary supplement, St. John’s Wort. This interaction has been reported to produce a marked reduction in the blood concentrations of cyclosporine, resulting in subtherapeutic levels, rejection of transplanted organs, and graft loss.


Rifabutin is known to increase the metabolism of other drugs metabolized by the cytochrome P-450 system. The interaction between rifabutin and cyclosporine has not been studied. Care should be exercised when these two drugs are administered concomitantly.


Nonsteroidal Anti-inflammatory Drug (NSAID) Interactions: Clinical status and serum creatinine should be closely monitored when cyclosporine is used with nonsteroidal anti-inflammatory agents in rheumatoid arthritis patients. (See WARNINGS.)


Pharmacodynamic interactions have been reported to occur between cyclosporine and both naproxen and sulindac, in that concomitant use is associated with additive decreases in renal function, as determined by 99mTc-diethylenetriaminepentaacetic acid (DTPA) and (p-aminohippuric acid) PAH clearances. Although concomitant administration of diclofenac does not affect blood levels of cyclosporine, it has been associated with approximate doubling of diclofenac blood levels and occasional reports of reversible decreases in renal function. Consequently, the dose of diclofenac should be in the lower end of the therapeutic range.


Methotrexate Interaction: Preliminary data indicate that when methotrexate and cyclosporine were co-administered to rheumatoid arthritis patients (N=20), methotrexate concentrations (AUCs) were increased approximately 30% and the concentrations (AUCs) of its metabolite, 7-hydroxy methotrexate, were decreased by approximately 80%. The clinical significance of this interaction is not known. Cyclosporine concentrations do not appear to have been altered (N=6).


Other Drug Interactions: Cyclosporine is an inhibitor of CYP3A4 and of the multidrug efflux transporterP-glycoprotein and may increase plasma concentrations of comedications that are substrates of CYP3A4 or P-glycoprotein or both.


Cyclosporine may reduce the clearance of digoxin, colchicine, prednisolone, HMG-CoA reductase inhibitors (statins) and etoposide. Severe digitalis toxicity has been seen within days of starting cyclosporine in several patients taking digoxin. There are also reports on the potential of cyclosporine to enhance the toxic effects of colchicine such as myopathy and neuropathy, especially in patients with renal dysfunction. If digoxin or colchicine are used concurrently with cyclosporine, close clinical observation is required in order to enable early detection of toxic manifestations of digoxin or colchicine, followed by reduction of dosage and its withdrawal.


Literature and postmarketing cases of myotoxicity, including muscle pain and weakness, myositis, and rhabdomyolysis, have been reported with concomitant administration of cyclosporine with lovastatin, simvastatin, atorvastatin, pravastatin, and, rarely, fluvastatin. When concurrently administered with cyclosporine, the dosage of these statins should be reduced according to label recommendations. Statin therapy needs to be temporarily withheld or discontinued in patients with signs and symptoms of myopathy or those with risk factors predisposing to severe renal injury, including renal failure, secondary to rhabdomyolysis. Cyclosporine should not be used with potassium-sparing diuretics because hyperkalemia can occur. Caution is also required when cyclosporine is co-administered with potassium sparing drugs (e.g., angiotensin-converting enzyme inhibitors, angiotensin II receptor antagonists), potassium-containing drugs as well as in patients on a potassium rich diet. Control of potassium levels in these situations is advisable.


Cyclosporine may increase the plasma concentrations of repaglinide and thereby increase the risk of hypoglycemia. In 12 healthy male subjects who received two doses of 100 mg cyclosporine capsule orally 12 hours apart with a single dose of 0.25 mg repaglinide tablet (one half of a 0.5 mg tablet) orally 13 hours after the cyclosporine initial dose, the repaglinide mean Cmax and AUC were increased 1.8 fold (range: 0.6 to 3.7 fold) and 2.4 fold (range 1.2 to 5.3 fold), respectively. Close monitoring of blood glucose level is advisable for a patient taking cyclosporine and repaglinide concomitantly.


Elevations in serum creatinine were observed in studies using sirolimus in combination with full-dose cyclosporine. This effect is often reversible with cyclosporine dose reduction. Simultaneous co-administration of cyclosporine significantly increases blood levels of sirolimus. To minimize increases in sirolimus blood concentrations, it is recommended that sirolimus be given 4 hours after cyclosporine administration.


During treatment with cyclosporine, vaccination may be less effective. The use of live vaccines should be avoided. Frequent gingival hyperplasia with nifedipine, and convulsions with high dose methylprednisolone have been reported.


Psoriasis patients receiving other immunosuppressive agents or radiation therapy (including PUVA and UVB) should not receive concurrent cyclosporine because of the possibility of excessive immunosuppression.



Carcinogenesis, mutagenesis, impairment of fertility


Cyclosporine gave no evidence of mutagenic or teratogenic effects in appropriate test systems.Only at dose levels toxic to dams, were adverse effects seen in reproduction studies in rats. (See Pregnancy.)


Carcinogenicity studies were carried out in male and female rats and mice. In the 78-week mouse study, at doses of 1, 4, and 16 mg/kg/day, evidence of a statistically significant trend was found for lymphocytic lymphomas in females, and the incidence of hepatocellular carcinomas in mid-dose males significantly exceeded the control value. In the 24-month rat study, conducted at 0.5, 2, and 8 mg/kg/day, pancreatic islet cell adenomas significantly exceeded the control rate in the low dose level. The hepatocellular carcinomas and pancreatic islet cell adenomas were not dose related.


No impairment in fertility was demonstrated in studies in male and female rats.


Cyclosporine has not been found mutagenic/genotoxic in the Ames Test, the V79-HGPRT Test, the micronucleus test in mice and Chinese hamsters, the chromosome-aberration tests in Chinese hamster bone-marrow, the mouse dominant lethal assay, and the DNA-repair test in sperm from treated mice. A recent study analyzing sister chromatid exchange (SCE) induction by cyclosporine using human lymphocytes in vitro gave indication of a positive effect (i.e., induction of SCE), at high concentrations in this system. In two published research studies, rabbits exposed to cyclosporine in utero (10 mg/kg/day subcutaneously) demonstrated reduced numbers of nephrons, renal hypertrophy, systemic hypertension and progressive renal insufficiency up to 35 weeks of age. Pregnant rats which received 12 mg/kg/day of cyclosporine intravenously (twice the recommended human intravenous dose) had fetuses with an increased incidence of ventricular septal defect. These findings have not been demonstrated in other species and their relevance for humans is unknown.


An increased incidence of malignancy is a recognized complication of immunosuppression in recipients of organ transplants. The most common forms of neoplasms are non-Hodgkin’s lymphoma and carcinomas of the skin. The risk of malignancies in cyclosporine recipients is higher than in the normal, healthy population but similar to that in patients receiving other immunosuppressive therapies. It has been reported that reduction or discontinuance of immunosuppression may cause the lesions to regress.



Pregnancy


Teratogenic effects

Pregnancy Category C


Animal studies have shown reproductive toxicity in rats and rabbits. Cyclosporine gave no evidence of mutagenic or teratogenic effects in the standard test systems with oral application (rats up to 17 mg/kg and rabbits up to 30 mg/kg per day orally). Cyclosporine oral solution has been shown to be embryo- and fetotoxic in rats and rabbits when given in doses 2 to 5 times the human dose. At toxic doses (rats at 30 mg/kg/day and rabbits at 100 mg/kg/day), cyclosporine oral solution was embryo- and fetotoxic as indicated by increased pre- and postnatal mortality and reduced fetal weight together with related skeletal retardations. In the well-tolerated dose range (rats at up to 17 mg/kg/day and rabbits at up to 30 mg/kg/day), cyclosporine oral solution proved to be without any embryolethal or teratogenic effects.


There are no adequate and well-controlled studies in pregnant women and, therefore, cyclosporine should not be used during pregnancy unless the potential benefit to the mother justifies the potential risk to the fetus.


In pregnant transplant recipients who are being treated with immunosuppressants, the risk of premature birth is increased. The following data represent the reported outcomes of 116 pregnancies in women receiving cyclosporine during pregnancy, 90% of whom were transplant patients, and most of whom received cyclosporine throughout the entire gestational period. Since most of the patients were not prospectively identified, the results are likely to be biased toward negative outcomes. The only consistent patterns of abnormality were premature birth (gestational period of 28 to 36 weeks) and low birth weight for gestational age. It is not possible to separate the effects of cyclosporine on these pregnancies from the effects of the other immunosuppressants, the underlying maternal disorders, or other aspects of the transplantation milieu. Sixteen fetal losses occurred. Most of the pregnancies (85 of 100) were complicated by disorders; including, preeclampsia, eclampsia, premature labor, abruptio placentae, oligohydramnios, Rh incompatibility and fetoplacental dysfunction. Preterm delivery occurred in 47%. Seven malformations were reported in 5 viable infants and in 2 cases of fetal loss. Twenty-eight percent of the infants were small for gestational age. Neonatal complications occurred in 27%. In a report of 23 children followed up to 4 years, postnatal development was said to be normal. A limited number of observations in children exposed to cyclosporine in utero is available, up to an age of approximately 7 years. Renal function and blood pressure in these children were normal.



Nursing mothers


Cyclosporine passes into breast milk. Mothers receiving treatment with cyclosporine should not breast feed.



Pediatric use


Although no adequate and well-controlled studies have been conducted in children, patients as young as 6 months of age have received the drug with no unusual adverse effects.



Geriatric use


Clinical studies of cyclosporine did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger patients. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.



Adverse Reactions


The principal adverse reactions of cyclosporine therapy are renal dysfunction, tremor, hirsutism, hypertension, and gum hyperplasia.


Hypertension, which is usually mild to moderate, may occur in approximately 50% of patients following renal transplantation and in most cardiac transplant patients.


Glomerular capillary thrombosis has been found in patients treated with cyclosporine and may progress to graft failure. The pathologic changes resemble those seen in the hemolytic-uremic syndrome and include thrombosis of the renal microvasculature, with platelet-fibrin thrombi occluding glomerular capillaries and afferent arterioles, microangiopathic hemolytic anemia, thrombocytopenia, and decreased renal function. Similar findings have been observed when other immunosuppressives have been employed posttransplantation.


Hypomagnesemia has been reported in some, but not all, patients exhibiting convulsions while on cyclosporine therapy. Although magnesium-depletion studies in normal subjects suggest that hypomagnesemia is associated with neurologic disorders, multiple factors, including hypertension, high dose methylprednisolone, hypocholesterolemia, and nephrotoxicity associated with high plasma concentrations of cyclosporine appear to be related to the neurological manifestations of cyclosporine toxicity.


The following reactions occurred in 3% or greater of 892 patients involved in clinical trials of kidney, heart, and liver transplants:

















































































































Randomized Kidney PatientsAll Cyclosporine Patients
Body System/Adverse Reactions

Cyclosporine (N=227)


%



Azathioprine (N=228)


%



Kidney (N=705)


%



Heart (N=112)


%



Liver (N=75)


%


Genitourinary
Renal Dysfunction326253837
Cardiovascular
Hypertension2618135327
Cramps4<12<10
Skin
Hirsutism21<1212845
Acne68221
Central Nervous System
Tremor120213155
Convulsions31145
Headache2<12154
Gastrointestinal
Gum Hyperplasia409516
Diarrhea3<1348
Nausea/Vomiting2<14104
Hepatotoxicity<1<1474

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