Mycophenolate Mofetil 500 mg Tablet, Film Coated, 500-count — NDC 0781-5175-05 (Billing 00781-5175-05)

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Mycophenolate mofetil (MMF) is absorbed following oral administration and hydrolyzed to mycophenolic acid (MPA), the active metabolite. MPA is a selective uncompetitive inhibitor of the two isoforms (type I and type II) of inosine monophosphate dehydrogenase (IMPDH) leading to inhibition of the de novo pathway of guanosine nucleotide synthesis and blocks DNA synthesis. The mechanism of action of MPA is multifaceted and includes effects on cellular checkpoints responsible for metabolic programming of lymphocytes.

MPA shifts transcriptional activities in lymphocytes from a proliferative state to catabolic processes. In vitro studies suggest that MPA modulates transcriptional activities in human CD4+ T-lymphocytes by suppressing the Akt/mTOR and STAT5 pathways that are relevant to metabolism and survival, leading to an anergic state of T-cells whereby the cells become less responsive to antigenic stimulation. Additionally, MPA enhanced the expression of negative co-stimulators such as CD70, PD-1, CTLA-4, and transcription factor FoxP3 as well as decreased the expression of positive co-stimulators CD27 and CD28.

MPA decreases proliferative responses of T- and B-lymphocytes to both mitogenic and allo-antigenic stimulation, antibody responses, as well as the production of cytokines from lymphocytes and monocytes such as GM-CSF, IFN- Ɣ , IL-17, and TNF-α. Additionally, MPA prevents the glycosylation of lymphocyte and monocyte glycoproteins that are involved in intercellular adhesion to endothelial cells and may inhibit recruitment of leukocytes into sites of inflammation and graft rejection. Overall, the effect of MPA is cytostatic and reversible.

12.2Pharmacodynamics There is a lack of information regarding the pharmacodynamic effects of MMF.

12.3Pharmacokinetics Absorption Following oral and intravenous administration, MMF undergoes complete conversion to MPA, the active metabolite. In 12 healthy volunteers, the mean absolute bioavailability of oral MMF relative to intravenous MMF was 94%. Two 500 mg mycophenolate mofetil tablets have been shown to be bioequivalent to four 250 mg mycophenolate mofetil capsules.

Five mL of the 200 mg/mL constituted mycophenolate mofetil oral suspension have been shown to be bioequivalent to four 250 mg capsules. The mean (±SD) pharmacokinetic parameters estimates for MPA following the administration of MMF given as single doses to healthy volunteers, and multiple doses to kidney, heart, and liver transplant patients, are shown in Table . The area under the plasma-concentration time curve (AUC) for MPA appears to increase in a dose-proportional fashion in kidney transplant patients receiving multiple oral doses of MMF up to a daily dose of 3 g (1.5g twice daily) (see Table 10 ).

Table 10. Pharmacokinetic Parameters for MPA [mean (±SD)] Following Administration of MMF to Healthy Volunteers (Single Dose), and Kidney, Heart, and Liver Transplant Patients (Multiple Doses) Healthy Volunteers Dose/Route T max (h) C max (mcg/mL) Total AUC (mcg∙h/mL) Single dose 1 g/oral 0.80 (±0.36) (n=129) 24.5 (±9.5) (n=129) 63.9 (±16.2) (n=117) Kidney Transplant Patients (twice daily dosing) Time After Transplantation Dose/Route T max (h) C max (mcg/mL) Interdosing Interval AUC ( 0–12h ) (mcg∙h/mL) 5 days 1 g/iv 1.58 (±0.46) (n=31) 12 (±3.82) (n=31) 40.8 (±11.4) (n=31) 6 days 1 g/oral 1.33 (±1.05) (n=31) 10.7 (±4.83) (n=31) 32.9 (±15) (n=31) Early (Less than 40 days) 1 g/oral 1.31 (±0.76) (n=25) 8.16 (±4.50) (n=25) 27.3 (±10.9) (n=25) Early (Less than 40 days) 1.5 g/oral 1.21 (±0.81) (n=27) 13.5 (±8.18) (n=27) 38.4 (±15.4) (n=27) Late (Greater than 3 months) 1.5 g/oral 0.90 (±0.24) (n=23) 24.1 (±12.1) (n=23) 65.3 (±35.4) (n=23) Heart transplant Patients (twice daily dosing) Time After Transplantation Dose/Route T max (h) C max (mcg/mL) Interdosing Interval AUC ( 0–12h ) (mcg∙h/mL) Early (Day before discharge) 1.5 g/oral 1.8 (±1.3) (n=11) 11.5 (±6.8) (n=11) 43.3 (±20.8)… [Excerpted — this section continues on DailyMed.]

12.1Mechanism of Action Mycophenolate mofetil (MMF) is absorbed following oral administration and hydrolyzed to mycophenolic acid (MPA), the active metabolite. MPA is a selective uncompetitive inhibitor of the two isoforms (type I and type II) of inosine monophosphate dehydrogenase (IMPDH) leading to inhibition of the de novo pathway of guanosine nucleotide synthesis and blocks DNA synthesis. The mechanism of action of MPA is multifaceted and includes effects on cellular checkpoints responsible for metabolic programming of lymphocytes.

MPA shifts transcriptional activities in lymphocytes from a proliferative state to catabolic processes. In vitro studies suggest that MPA modulates transcriptional activities in human CD4+ T-lymphocytes by suppressing the Akt/mTOR and STAT5 pathways that are relevant to metabolism and survival, leading to an anergic state of T-cells whereby the cells become less responsive to antigenic stimulation. Additionally, MPA enhanced the expression of negative co-stimulators such as CD70, PD-1, CTLA-4, and transcription factor FoxP3 as well as decreased the expression of positive co-stimulators CD27 and CD28.

MPA decreases proliferative responses of T- and B-lymphocytes to both mitogenic and allo-antigenic stimulation, antibody responses, as well as the production of cytokines from lymphocytes and monocytes such as GM-CSF, IFN- Ɣ , IL-17, and TNF-α. Additionally, MPA prevents the glycosylation of lymphocyte and monocyte glycoproteins that are involved in intercellular adhesion to endothelial cells and may inhibit recruitment of leukocytes into sites of inflammation and graft rejection. Overall, the effect of MPA is cytostatic and reversible.

12.3Pharmacokinetics Absorption Following oral and intravenous administration, MMF undergoes complete conversion to MPA, the active metabolite. In 12 healthy volunteers, the mean absolute bioavailability of oral MMF relative to intravenous MMF was 94%. Two 500 mg mycophenolate mofetil tablets have been shown to be bioequivalent to four 250 mg mycophenolate mofetil capsules.

Five mL of the 200 mg/mL constituted mycophenolate mofetil oral suspension have been shown to be bioequivalent to four 250 mg capsules. The mean (±SD) pharmacokinetic parameters estimates for MPA following the administration of MMF given as single doses to healthy volunteers, and multiple doses to kidney, heart, and liver transplant patients, are shown in Table . The area under the plasma-concentration time curve (AUC) for MPA appears to increase in a dose-proportional fashion in kidney transplant patients receiving multiple oral doses of MMF up to a daily dose of 3 g (1.5g twice daily) (see Table 10 ).

Table 10. Pharmacokinetic Parameters for MPA [mean (±SD)] Following Administration of MMF to Healthy Volunteers (Single Dose), and Kidney, Heart, and Liver Transplant Patients (Multiple Doses) Healthy Volunteers Dose/Route T max (h) C max (mcg/mL) Total AUC (mcg∙h/mL) Single dose 1 g/oral 0.80 (±0.36) (n=129) 24.5 (±9.5) (n=129) 63.9 (±16.2) (n=117) Kidney Transplant Patients (twice daily dosing) Time After Transplantation Dose/Route T max (h) C max (mcg/mL) Interdosing Interval AUC ( 0–12h ) (mcg∙h/mL) 5 days 1 g/iv 1.58 (±0.46) (n=31) 12 (±3.82) (n=31) 40.8 (±11.4) (n=31) 6 days 1 g/oral 1.33 (±1.05) (n=31) 10.7 (±4.83) (n=31) 32.9 (±15) (n=31) Early (Less than 40 days) 1 g/oral 1.31 (±0.76) (n=25) 8.16 (±4.50) (n=25) 27.3 (±10.9) (n=25) Early (Less than 40 days) 1.5 g/oral 1.21 (±0.81) (n=27) 13.5 (±8.18) (n=27) 38.4 (±15.4) (n=27) Late (Greater than 3 months) 1.5 g/oral 0.90 (±0.24) (n=23) 24.1 (±12.1) (n=23) 65.3 (±35.4) (n=23) Heart transplant Patients (twice daily dosing) Time After Transplantation Dose/Route T max (h) C max (mcg/mL) Interdosing Interval AUC ( 0–12h ) (mcg∙h/mL) Early (Day before discharge) 1.5 g/oral 1.8 (±1.3) (n=11) 11.5 (±6.8) (n=11) 43.3 (±20.8) (n=9) Late (Greater than 6 months) 1.5 g/oral 1.1 (±0.7) (n=52) 20 (±9.4) (n=52) 54.1 * (±20.4) (n=49) Liver transplant Patients (twice daily dosing) Time After Transplantation Dose/Route T max (h) C max (mcg/mL) Interdosing Interval AUC ( 0–12h ) (mcg∙h/mL) 4 to 9 days 1 g/iv 1.50 (±0.517) (n=22) 17 (±12.7) (n=22) 34 (±17.4) (n=22) Early (5 to 8 days) 1.5 g/oral 1.15 (±0.432) (n=20) 13.1 (±6.76) (n=20) 29.2 (±11.9) (n=20) Late (Greater than 6 months) 1.5 g/oral 1.54 (±0.51) (n=6) 19.3 (±11.7) (n=6) 49.3 (±14.8) (n=6) *AUC(0-12h) values quoted are extrapolated from data from samples collected over 4 hours.

In the early post-transplant period (less than 40 days post-transplant), kidney, heart, and liver transplant patients had mean MPA AUCs approximately 20% to 41% lower and mean C max approximately 32% to 44% lower compared to the late transplant period (i.e., 3 to 6 months post-transplant) (non-stationarity in MPA pharmacokinetics). Mean MPA AUC values following administration of 1 g twice daily intravenous mycophenolate mofetil over 2 hours to kidney transplant patients for 5 days were about 24% higher than those observed after oral administration of a similar dose in the immediate post-transplant phase.

In liver transplant patients, administration of 1 g twice daily intravenous mycophenolate mofetil followed by 1.5 g twice daily oral mycophenolate mofetil resulted in mean MPA AUC estimates similar to those found in kidney transplant patients administered 1 g mycophenolate mofetil twice daily. Effect of Food Food (27 g fat, 650 calories) had no effect on the extent of absorption (MPA AUC) of MMF when administered at doses of 1.5 g twice daily to kidney transplant patients. However, MPA C max was decreased by 40% in the presence of food [see Dosage and Administration ( 2.1 )].

Distribut… [Excerpted — this section continues on DailyMed.]

12.2Pharmacodynamics There is a lack of information regarding the pharmacodynamic effects of MMF.

14 CLINICAL STUDIES

14.1Kidney Transplantation Adults The three de novo kidney transplantation studies compared two dose levels of oral mycophenolate mofetil (1 g twice daily and 1.5 g twice daily) with azathioprine (2 studies) or placebo (1 study) to prevent acute rejection episodes. One of the two studies with azathioprine (AZA) control arm also included anti-thymocyte globulin (ATGAM ® ) induction therapy. The geographic location of the investigational sites of these studies are included in Table 13 .

In all three de novo kidney transplantation studies, the primary efficacy endpoint was the proportion of patients in each treatment group who experienced treatment failure within the first 6 months after transplantation. Treatment failure was defined as biopsy-proven acute rejection on treatment or the occurrence of death, graft loss or early termination from the study for any reason without prior biopsy-proven rejection. Mycophenolate mofetil, in combination with corticosteroids and cyclosporine, reduced (statistically significant at 0.05 level) the incidence of treatment failure within the first 6 months following transplantation ( Table 13 ).

Patients who prematurely discontinued treatment were followed for the occurrence of death or graft loss, and the cumulative incidence of graft loss and patient death combined are summarized in Table 14 . Patients who prematurely discontinued treatment were not followed for the occurrence of acute rejection after termination. Table 13.

Treatment Failure in De Novo Kidney Transplantation Studies USA Study (N=499 patients) Mycophenolate mofetil 2 g/day (n=167 patients) Mycophenolate mofetil 3 g/day (n=166 patients) AZA 1 to 2 mg/kg/day (n=166 patients) All 3 groups received anti-thymocyte globulin induction, cyclosporine and corticosteroids All treatment failures 31.1% 31.3% 47.6% Early termination without prior acute rejection 9.6% 12.7% 6% Biopsy-proven rejection episode on treatment 19.8% 17.5% 38% Europe/Canada/ Australia Study (N=503 patients) Mycophenolate mofetil 2 g/day (n=173 patients) Mycophenolate mofetil 3 g/day (n=164 patients) AZA 100 to 150 mg/day (n=166 patients) No induction treatment administered; all 3 groups received cyclosporine and corticosteroids.

All treatment failures 38.2% 34.8% 50% Early termination without prior acute rejection 13.9% 15.2% 10.2% Biopsy-proven rejection episode on treatment 19.7% 15.9% 35.5% Europe Study (N=491 patients) Mycophenolate mofetil 2 g/day (n=165 patients) Mycophenolate mofetil 3 g/day (n=160 patients) Placebo (n=166 patients) No induction treatment administered; all 3 groups received cyclosporine and corticosteroids. All treatment failures 30.3% 38.8% 56% Early termination without prior acute rejection 11.5% 22.5% 7.2% Biopsy-proven rejection episode on treatment 17% 13.8% 46.4% *Does not include death and graft loss as reason for early termination.

No advantage of mycophenolate mofetil at 12 months with respect to graft loss or patient death (combined) was established ( Table 14 ). Numerically, patients receiving mycophenolate mofetil 2 g/day and 3 g/day experienced a better outcome than controls in all three studies; patients receiving mycophenolate mofetil 2 g/day experienced a better outcome than mycophenolate mofetil 3 g/day in two of the three studies. Patients in all treatment groups who terminated treatment early were found to have a poor outcome with respect to graft loss or patient death at 1 year.

Table 14. De Novo Kidney Transplantation Studies Cumulative Incidence of Combined Graft Loss or Patient Death at 12 Months Study Mycophenolate mofetil 2 g/day Mycophenolate mofetil 3 g/day Control (AZA or Placebo) USA 8.5% 11.5% 12.2% Europe/Canada/Australia 11.7% 11% 13.6% Europe 8.5% 10% 11.5% Pediatrics-De Novo Kidney transplantation PK Study with Long Term Follow-Up One open-label, safety and pharmacokinetic study of mycophenolate mofetil oral suspension 600 mg/m 2 twice daily (up to 1 g twice daily) in combination with cycl… [Excerpted — this section continues on DailyMed.]

13 NONCLINICAL TOXICOLOGY

13.1Carcinogenesis, Mutagenesis, Impairment of Fertility In a 104-week oral carcinogenicity study in mice, MMF in daily doses up to 180 mg/kg was not tumorigenic. The highest dose tested was 0.2 times the recommended clinical dose (2 g/day) in renal transplant patients and 0.15 times the recommended clinical dose (3 g/day) in cardiac transplant patients when corrected for differences in body surface area (BSA). In a 104-week oral carcinogenicity study in rats, MMF in daily doses up to 15 mg/kg was not tumorigenic.

The highest dose was 0.035 times the recommended clinical dose in kidney transplant patients and 0.025 times the recommended clinical dose in heart transplant patients when corrected for BSA. While these animal doses were lower than those given to patients, they were maximal in those species and were considered adequate to evaluate the potential for human risk [see Warnings and Precautions ( 5.2 )]. The genotoxic potential of MMF was determined in five assays.

MMF was genotoxic in the mouse lymphoma/thymidine kinase assay and the in vivo mouse micronucleus assay. MMF was not genotoxic in the bacterial mutation assay, the yeast mitotic gene conversion assay or the Chinese hamster ovary cell chromosomal aberration assay. MMF had no effect on fertility of male rats at oral doses up to 20 mg/kg/day.

This dose represents 0.05 times the recommended clinical dose in renal transplant patients and 0.03 times the recommended clinical dose in cardiac transplant patients when corrected for BSA. In a female fertility and reproduction study conducted in rats, oral doses of 4.5 mg/kg/day caused malformations (principally of the head and eyes) in the first generation offspring in the absence of maternal toxicity. This dose was 0.01 times the recommended clinical dose in renal transplant patients and 0.005 times the recommended clinical dose in cardiac transplant patients when corrected for BSA.

No effects on fertility or reproductive parameters were evident in the dams or in the subsequent generation.