Mycophenolic acid
Summary
Persistence. Mycophenolic acid is slowly degraded in the environment.
Bioaccumulation. Mycophenolic acid has low potential for bioaccumulation.
Toxicity. Mycophenolic acid has very high chronic toxicity.
Risk. The use of mycophenolic acid (sales data Sweden 2021) has been considered to result in moderate environmental risk.
This summary information comes from Fass.
Detailed information
Mycophenolate mofetil and sodium mycophenolate
According to the Fass for Cellcept (mycophenolic acid): After oral administration, mycophenolate mofetil is rapidly and completely absorbed. Presystemically, mycophenolate mofetil is completely metabolized to the active metabolite, MPA. MPA = mycophenolic acid. MPA is mainly metabolized by glucuronyl transferase (isoform UGT1A9) to the inactive phenol glucuronide of MPA (MPAG). […] Most (about 87%) of the administered dose was excreted in urine as MPAG. Glucuronide conjugates can be split off in waste water treatment plants and generate active substance again (Larsson et al, 1999). Sodium mycophenolate dissociates in an aqueous phase to mycophenolic acid. The interesting substance from an environmental point of view should be mycophenolic acid.
Comment on Fass environmental information
Mycophenolic acid has different classifications on fass.se. According to Lif (the trade association for the research-based pharmaceutical industry in Sweden) the various pharmaceutical companies compile environmental information for their active substances based on internal studies and published data. Based on data, which may thus differ between different pharmaceutical companies, the companies assess the environmental risk with guidance from “Environmental classification of pharmaceuticals at www.fass.se – Guidance for pharmaceutical companies 2012”. The Swedish Environmental Institute (IVL) reviews the assessment but does not have the task of coordinating/harmonizing environmental information from different pharmaceutical companies for the same active substance.
Fass environmental information for Myfortic
Fass environmental information for Myfortic from Novartis (mycophenolic acid) (downloaded 2023-09-19).
Hazard
Persistence: "2.0–5.0 % degradation in 28 days, not readily biodegradable (OECD301)."
Bioaccumulation: Log P: 1.6 (method unknown, no reference available).
Chronic toxicity: There are data for 3 trophic levels, lowest for fish (zebrafish; Danio rerio) 1.32 microg/L.
Risk
PEC/PNEC is based on sales data in Sweden in year 2021. PEC/PNEC = 2.99 ~ 3.0 which gives the risk moderate.
Fass environmental information for Cellcept
Fass environmental information for Cellcept from Roche (mycophenolic acid) (downloaded 2023-09-19).
Hazard
Persistence: Mycophenolate mofetil/Mycophenolic acid is not readily degradable. In sediment/water fate systems significant removal (up to >50%) of radio-labelled MPA was noted after 64 days. There is additional evidence for some aquatic photodegradation. In a biodegradation test in activated sludge according to OECD 314B a mineralisation of 82% was observed within 28 days. This justifies the phrase 'Mycophenolate mofetil/Mycophenolic acid is slowly degraded in the environment.'
Bioaccumulation: Log Dow = 2.28 (pH 5, 25 °C) (OECD 107)
= 0.47-0.48 (pH 7, 25 °C) (OECD 107)
= -1.83 - -1.54 (pH 9, 25 °C) (OECD 107)
Mycophenolate mofetil/Mycophenolic acid has low potential for bioaccumulation (log KOW < 4).
Chronic toxicity: There are data for 3 trophic levels, lowest for fish (zebrafish; Danio rerio) 5.8 microg/L.
Risk
PEC/PNEC is based on sales data in Sweden in year 2021. PEC/PNEC = 0.6 which gives the risk low.
Assessment report
Assessment report for Myclausen (mycophenolate mofetil), EMA/CHMP/451012/2010.
"An Environmental Risk Assessment has been submitted by the applicant. Myclausen is a generic product, which is deemed interchangeable with already marketed products, and is unlikely to increase the combined sales volumes of mycophenolate mofetil-containing products thus not having an adverse effect on the environment."
References
- Fass.se för vårdpersonal.
- Larsson DGJ, Adolfsson-Erici M, Parkkonen J, et al. Ethinyloestradiol — an undesired fish contraceptive? Aquatic Toxicology 1999; 45: 91–97.
- European Medicines Agency. European public assessment report (EPAR) for Myclausen EMA/CHMP/451012/2010.
Author: Health and Medical Care Administration, Region Stockholm