Changing treatment protocol from azathioprine to mycophenolate mofetil: decrease in renal dysfunction, increase in infections

SARS-CoV-2 infection risk is higher in vaccinated patients with inflammatory autoimmune diseases or liver transplantation treated with mycophenolate due to an impaired antiviral immune response: results of the extended follow up of the RIVALSA prospective cohort

Background

A relevant proportion of immunocompromised patients did not reach a detectable seroconversion after a full primary vaccination cycle against SARS-CoV-2. The effect of different immunosuppressants and the potential risks for SARS-CoV-2 infection in these subjects is largely unknown.

Methods

Patients from the Rivalsa prospective, observational cohort study with planned anti SARS-CoV-2 third dose mRNA vaccination between October and December 2021 were asked to participate to this follow-up study. Patients were asked about eventual confirmed positivity to SARS-CoV-2 infection within 6 months from the third dose and to undergo a blood draw to evaluate seroconversion status after the additional vaccine shot.

Results

19 out of 114 patients taking part in the survey developed a confirmed SARS-CoV-2 infection; we identified mycophenolate treatment as an independent predictor of an increased risk of infection even after the third vaccine dose (OR: 5.20, 95% CI: 1.70-20.00, p=0.0053). This result is in agreement with the in vitro evidence that MMF impairs both B and T lymphocytes driven immune responses (reduction both in memory B cells producing anti-spike antibodies and in proliferating CD4+ and CD8+ T cells).

Conclusions

Immunocompromised patients need an additional vaccine administration to reach a detectable seroconversion, thus fostering a more personalized approach to their clinical management. Moreover, patients undergoing mycophenolate treatment show a specific increased infection risk, with respect to other immunosuppressants thus supporting a closer monitoring of their health status.

Adverse Effects of Immunosuppression: Infections

Immunosuppressive therapies are currently indicated for a wide range of diseases. As new agents emerge and indications evolve the landscape grows increasingly complex. Therapies can target pathologic immune system over-activation in rheumatologic or autoimmune disease, or conditioning and graft versus host disease (GVHD) prophylactic regimens may eliminate or inhibit host immune function to improve graft survival and risk of complication in solid organ transplantation (SOT) or hematopoietic stem cell transplantation (HSCT). With immunosuppressive therapy, infections occur. Complex disease states, host factors, and concomitant therapies contribute to a "net state" of immunosuppression that must be considered and may confound perceived increased infection risks in patients receiving treatment.

Mining reported adverse events induced by potential opioid-drug interactions

OBJECTIVE

Opioid-based analgesia is routinely used in clinical practice for the management of pain and alleviation of suffering at the end of life. It is well-known that opioid-based medications can be highly addictive, promoting not only abuse but also life-threatening overdoses. The scope of opioid-related adverse events (AEs) beyond these well-known effects remains poorly described. This exploratory analysis investigates potential AEs from drug-drug interactions between opioid and nonopioid medications (ODIs).

MATERIALS AND METHODS

In this study, we conduct an initial exploration of the association between ODIs and severe AEs using millions of AE reports available in FDA Adverse Event Reporting System (FAERS). The odds ratio (OR)-based analysis and visualization are proposed for single drugs and pairwise ODIs to identify associations between AEs and ODIs of interest. Moreover, the multilabel (multi-AE) learning models are employed to evaluate the feasibility of AE prediction of polypharmacy.

RESULTS

The top 12 most prescribed opioids in the FAERS are identified. The OR-based analysis identifies a diverse set of AEs associated with individual opioids. Moreover, the results indicate many ODIs can increase the risk of severe AEs dramatically. The area under the curve values of multilabel learning models of ODIs for oxycodone varied between 0.81 and 0.88 for 5 severe AEs.

CONCLUSIONS

The proposed data analysis and visualization are useful for mining FAERS data to identify novel polypharmacy associated AEs, as shown for ODIs. This approach was successful in recapitulating known drug interactions and also identified new opioid-specific AEs that could impact prescribing practices.

Side effects and efficacy of renal sparing immunosuppression in pediatric liver transplantation-A single center matched cohort study

Immunosuppressive combination therapy with MMF can reduce CNI associated nephrotoxicity. We investigated effectiveness and safety of de novo MMF-tacrolimus based immunosuppression after pLTx. Patients after pLTx receiving immunosuppression with MMF/tacrolimus (MMF/TAC) were compared to retrospectively selected age- and diagnosis-matched patients with tacrolimus monotherapy (TAC) and cyclosporine/prednisolone therapy (CSA) (19 patients each, n = 57). Effectiveness, renal function and side effects were analyzed for 1 year after pLTx. Tacrolimus reduction in combination therapy (0.7 μg/L over the year) was lower than aspired (2 μg/L). Acute BPAR occurred equally in MMF/TAC and TAC groups (31.6% each), being slightly higher in CSA group (42.1%; OR = 1.5; 95% CI = 0.42-5.44; P = .5). GFR deteriorated comparably in all 3 groups (P < .01 each) without significant differences between the groups. Septicemia was detected significantly more often in MMF/TAC (73.6%) than in TAC (31.6%) (OR 4.17; 1.07-16.27; P = .04). EBV reactivation occurred more often in CSA patients (84.2%) than in MMF/TAC (47.4%; OR 5.16; 0.98-27.19; P = .05) and TAC patients (52.6%; OR 8.16; 1.48-44.89; P = .02) the same was true for other viral infections (47.4% (CSA) vs 15.8% (TAC); OR 4.21; 0.95-18.55; P = .05). Our study does not provide additional evidence for a benefit of initial use of MMF/TAC over TAC regarding renal function, but raises concerns regarding a potentially increased risk of serious infections under MMF/TAC compared to TAC monotherapy at equivalent renal outcome; our study is, however, limited by the minor CNI reduction in combination therapy.

Systemic inflammatory response in a liver transplant recipient: a potential side effect of mycophenolate mofetil

Mycophenolate mofetil is a commonly used immunosuppressive medication in the postliver transplant setting where gastrointestinal side effects tend to predominate. However, in more recent times, emerging and rare side effects are being reported in the literature. We present a case of a patient who had a significant inflammatory response and associated marked weight loss with the uptitration in dose of mycophenolate mofetil. Extensive investigations were performed to exclude other infective, inflammatory or malignant aetiologies for these symptoms, however no other cause was identified. The patient had the medication ceased and subsequently had a dramatic improvement in his inflammatory markers and regained the weight lost while on the medication.

Incidence and risk factors for herpes zoster in patients undergoing liver transplantation

BACKGROUND

Herpes zoster (HZ) is the most common manifestation of latent varicella zoster virus reactivation, which occurs naturally as a result of aging or in immunocompromised patients. Solid organ transplant recipients are at increased risk for HZ owing to their chronic immunosuppression. Although several reports investigated risk factors for the development of HZ in heart or renal transplantation, data in liver transplantation (LT) are limited.

METHODS

We evaluated clinical data retrospectively in 377 adult patients undergoing LT between January 2005 and December 2012 in our institution. We analyzed the incidence rate of HZ and the standardized incidence ratio (SIR) by comparing with the general Japanese population. We additionally investigated risk factors for HZ after LT.

RESULTS

HZ developed in 27 (7.16%) of the 377 patients after LT. The incidence rate of HZ after LT was 17.83 per 1000 person-years, which was significantly higher than in the general Japanese population (SIR = 4.61; 95% confidence interval [CI], 4.13-5.14). Multivariate analysis showed that older age (hazard ratio [HR] = 3.95; P < 0.001) and exposure to mycophenolate mofetil (HR = 3.03; P = 0.007) were independent risk factors for HZ after LT.

CONCLUSIONS

This is the first and largest study, to our knowledge, to investigate the incidence rate of HZ and risk factors for development of HZ after LT in the Japanese population. Further investigations to focus on immunosuppressive regimens to reduce the risk for HZ incidence in this high-risk population could establish a new protocol of immunosuppression after LT.

Time dependent neuroprotection of mycophenolate mofetil: effects on temporal dynamics in glial proliferation, apoptosis, and scar formation

Background

Immunosuppressants such as mycophenolate mofetil (MMF) have the capacity to inhibit microglial and astrocytic activation and to reduce the extent of cell death after neuronal injury. This study was designed to determine the effective neuroprotective time frame in which MMF elicits its beneficial effects, by analyzing glial cell proliferation, migration, and apoptosis.

Methods

Using organotypic hippocampal slice cultures (OHSCs), temporal dynamics of proliferation and apoptosis after N-methyl-D-aspartate (NMDA)-mediated excitotoxicity were analyzed by quantitative morphometry of Ki-67 or cleaved caspase-3 immunoreactive glial cells. Treatment on NMDA-lesioned OHSCs with mycophenolate mofetil (MMF)100 μg/mL was started at different time points after injury or performed within specific time frames, and the numbers of propidium iodide (PI)⁺ degenerating neurons and isolectin (I)B₄⁺ microglial cells were determined. Pre-treatment with guanosine 100 μmol/l was performed to counteract MMF-induced effects. The effects of MMF on reactive astrocytic scar formation were investigated in the scratch-wound model of astrocyte monolayers.

Results

Excitotoxic lesion induction led to significant increases in glial proliferation rates between 12 and 36 hours after injury and to increased levels of apoptotic cells between 24 and 72 hours after injury. MMF treatment significantly reduced glial proliferation rates without affecting apoptosis. Continuous MMF treatment potently reduced the extent of neuronal cell demise when started within the first 12 hours after injury. A crucial time-frame of significant neuroprotection was identified between 12 and 36 hours after injury. Pre-treatment with the neuroprotective nucleoside guanosine reversed MMF-induced antiproliferative effects on glial cells. In the scratch-wound model, gap closure was reached within 48 hours in controls, and was potently inhibited by MMF.

Conclusions

Our data indicate that immunosuppression by MMF significantly attenuates the extent of neuronal cell death when administered within a crucial time frame after injury. Moreover, long-lasting immunosuppression, as required after solid-organ transplantation, does not seem to be necessary. Targeting inosine 5-monophosphate dehydrogenase, the rate-limiting enzyme of purine synthesis, is an effective strategy to modulate the temporal dynamics of proliferation and migration of microglia and astrocytes, and thus to reduce the extent of secondary neuronal damage and scar formation.

Characteristics of long-term immunosuppressive therapy in Chinese pediatric renal transplant patients: a single-center experience

We performed this study to investigate the trend and characteristics of various immunosuppressive regimens as well as their efficacy and safety for long-term survival of Chinese pediatric renal allograft recipients.

METHODS

Thirty-four patients who underwent kidney transplantation between January 1985 and July 2002 had >/=5 years follow up. We retrospectively reviewed the baseline characteristics, patient and kidney survival rates, renal function, immunosuppressive regimens, drug levels, and adverse effects of immunosuppressive medications.

RESULTS

The 1-, 3-, and 5-year recipient versus graft survival rates were 100% and 97.1%; 91.2% and 88.2%; 85.3% and 82.4%, respectively. The proportions of patients treated with cyclosporine- or tacrolimus-based immunosuppressive regimen at these times were 48.5%/51.5%; 60.0%/40.0%; and 53.6/46.4%. There were no significant differences in the dosages and drug levels after 1 year (P > .05). The proportions of azathioprine versus mycophenolate mofetil adjunctive therapy were 21.3/78.8%; 23.3%/70%; and 32.1%/60.7%, respectively. Forty percent of the surviving recipients developed complications, including hypertension, hyperlipidemia, gingival hyperplasia, hirsutism, liver dysfunction, herpes zoster, diabetes mellitus or cataracts.

CONCLUSIONS

Cyclosporine or tacrolimus, plus mycophenolate mofetil or azathioprine, and prednisone triple therapies showed promising long-term results with similar efficacy and safety in pediatric renal recipients. Periodic drug level monitoring is required to facilitate individualization of immunosuppressive regimens. Drug doses and levels differed markedly from non-Chinese patients because of the ethnic discrepancy.

Mycophenolate mofetil: effects on cellular immune subsets, infectious complications, and antimicrobial activity

Mycophenolate mofetil (MMF) is one of the most frequently used immunosuppressive drugs in solid organ transplant recipients. MMF is an inhibitor of inosine-5'-monophosphate, and is able to preferentially inhibit B-cell and T-cell function. The immunosuppressive abilities of MMF have made it one of the most successful anti-rejection drugs in transplant patients, but patients also appear to have increased susceptibility to infections, specifically cytomegalovirus and BK virus. Despite its association with an increased risk of infection, MMF has also exhibited antimicrobial activity against pathogens including hepatitis C, Pneumocystis jirovecii, and human immunodeficiency virus. A thorough understanding of the functions of MMF on the immune system and interaction with infectious pathogens could be helpful in implementing preventative strategies against opportunistic infections in transplant patients.

Tapering immunosuppressive therapy significantly improves in vivo cutaneous delayed type hypersensitivity responses

Immunosuppressive therapy affects cell-mediated immunity and thereby increases the frequency of infections and malignancies in transplanted patients. We questioned whether reducing the immunosuppressive dose in stable kidney transplant patients has an in vivo effect on cutaneous delayed type hypersensitivity responses (DTH) reflecting cell-mediated immunity. We measured DTH responses to recall antigens (Tetanus, Diphteria, Streptococcus, Tuberculin, Candida, Trychophyton, Proteus, glycerin control) on the volar surface of the forearm in patients before and after successful reduction (50%) of the dose of mycophenolate mofetil (MMF) or azathioprine (AZA). In addition, we tested healthy individuals who were age- and sex-matched to the patient group. Results of the skin reaction test were calculated as the sum in millimeters (mm) of all positive reactions (score), and as the number of positive antigens. Patients treated with a high dose of MMF or AZA had a significantly lower test score compared to healthy controls (p=0.01). Also the number of positive antigens was reduced in patients compared to healthy controls (p=0.02). After reduction of the MMF or AZA dose, the test score and the number of positive antigens increased significantly (p=0.02, p=0.01, respectively) to comparable scores of healthy controls. Additionally, the mycophenolic acid (MPA) trough level was negatively correlated with the test score (p=0.006) and number of positive antigens (p=0.004). In conclusion, successful tapering of the MMF or AZA dose in kidney transplant patients more than 2 years after transplantation favorably affects the in vivo DTH response, reflecting an improvement of the general immunity, facilitating the defense against infection and malignancies.