Lack of clinically significant interactions between concomitantly administered rasagiline and escitalopram

Concurrent administration of serotonergic antidepressants and ozanimod in participants with relapsing multiple sclerosis from the open-label extension DAYBREAK trial

BACKGROUND

Monoamine oxidase (MAO) inhibitors can interact with selective serotonin reuptake inhibitors (SSRIs)/serotonin-norepinephrine reuptake inhibitors (SNRIs). There is clinical interest surrounding use of ozanimod with SSRIs/SNRIs because the major metabolites of ozanimod are weak inhibitors of MAO-B in vitro.

OBJECTIVE

To evaluate the incidence of treatment-emergent adverse events (TEAEs) potentially related to serotonin accumulation (SA) during concomitant ozanimod and SSRI/SNRI use by performing analyses of data from an open-label, oral ozanimod 0.92 mg trial (DAYBREAK; NCT02576717).

METHODS

SA narrow (serotonin syndrome, neuroleptic malignant syndrome, and hyperthermia malignant) and broad (terms potentially associated with SA) MedDRA v24.0 searches were performed using TEAE data from participants with relapsing multiple sclerosis who entered DAYBREAK from phase 3 studies (cutoff February 1, 2022). Incidences of TEAEs matching terms from each search were stratified by SSRI/SNRI use.

RESULTS

Of 2257 DAYBREAK participants, 274 (12.1%) used an SSRI/SNRI. No participants had TEAEs matching the SA narrow search terms. There was no significant difference in the percentage of participants with ⩾1 TEAE matching the SA broad search for those on versus off SSRIs/SNRIs (on: 12.4%, n = 34/274; off: 15.6%, n = 310/1982, nominal p = 0.1630).

CONCLUSION

MedDRA searches showed no increase in TEAEs potentially associated with SA with concomitant SSRI/SNRI and ozanimod use.

A Case Report on Serotonin Syndrome in a Patient With Parkinson’s Disease: Diagnostic and Management Challenges

Patients with Parkinson's disease are often at risk of polypharmacy, which can lead to serious medication side effects and interactions. Serotonin syndrome (SS) can develop in this patient population due to a possible drug-drug interaction between antidepressants and antiparkinson drugs with serotoninergic activity. On the other hand, these patients are also at risk of malignant syndrome (MS) secondary to dopaminergic medication withdrawal. In this case report, we present a 71-year-old female with Parkinson's disease who developed symptoms suggestive of SS. The patient was admitted to the medical intensive care unit at the Institute for Pulmonary Diseases of Vojvodina in the Republic of Serbia due to impaired consciousness and a previously witnessed cardiorespiratory arrest. Her chronic antiparkinson medication regimen consisted of levodopa, benserazide, entacapone, ropinirole, and rasagiline. Furthermore, she had been prescribed duloxetine for a remote history of depression, which she had only been taking intermittently. Several days before admission, however, the patient started taking duloxetine again due to low mood. Upon admission, laboratory tests revealed leukocytosis with neutrophilia, elevated C-reactive protein, procalcitonin, lactate, urea, and creatinine. Serum creatine kinase (CK) levels were also elevated at 1250 U/L. Six hours after admission to the ICU, the patient developed hyperthermia, hyperreflexia, spontaneous myoclonus, and tremors. Her CK levels continued to rise, reaching 6900 U/L, and her renal function worsened. Due to the possibility of either SS or MS, external cooling measures with frozen gel packs were administered, resulting in the patient's stabilization over a few hours. Further, serotoninergic medication (rasagiline and duloxetine) was discontinued. On the fifth day of hospitalization, a head CT showed signs of cytotoxic edema. On the 11th day, the patient became hemodynamically unstable and passed away despite all adequate resuscitative measures. The purpose of this case report is to raise awareness of possible SS in patients taking monoamine oxidase-B (MAO-B) inhibitors such as rasagiline. Clinicians should have a high index of suspicion for this complication, especially in patients who are treated for comorbid depression with serotoninergic drugs. Furthermore, we emphasize the importance of correctly differentiating SS from MS, which are both risks for patients with Parkinson's disease. A correct approach to these patients is of utmost importance for adequate management and optimal outcomes.

Dopaminergic Therapy for Motor Symptoms in Early Parkinson Disease Practice Guideline Summary: A Report of the AAN Guideline Subcommittee

BACKGROUND AND OBJECTIVES

To review the current evidence on the options available for initiating dopaminergic treatment of motor symptoms in early-stage Parkinson disease and provide recommendations to clinicians.

METHODS

A multidisciplinary panel developed practice recommendations, integrating findings from a systematic review and following an Institute of Medicine-compliant process to ensure transparency and patient engagement. Recommendations were supported by structured rationales, integrating evidence from the systematic review, related evidence, principles of care, and inferences from evidence.

RESULTS

Initial treatment with levodopa provides superior motor benefit compared to treatment with dopamine agonists, whereas levodopa is more likely than dopamine agonists to cause dyskinesia. The comparison of different formulations of dopamine agonists yielded little evidence that any one formulation or method of administration is superior. Long-acting forms of levodopa and levodopa with entacapone do not appear to differ in efficacy from immediate-release levodopa for motor symptoms in early disease. There is a higher risk of impulse control disorders associated with the use of dopamine agonists than levodopa. Recommendations on initial therapy for motor symptoms are provided to assist the clinician and patient in choosing between treatment options and to guide counseling, prescribing, and monitoring of efficacy and safety.

Interaction between Monoamine Oxidase B Inhibitors and Selective Serotonin Reuptake Inhibitors

BACKGROUND

Monoamine oxidase B (MAO-B) inhibitors are used to treat the motor symptoms of Parkinson disease. Depression is commonly associated with Parkinson disease, and selective serotonin reuptake inhibitors (SSRIs) are often used for its management. Tertiary sources warn that the combination of MAO-B inhibitors and SSRIs can result in increased serotonergic effects, leading to serotonin syndrome.

OBJECTIVE

To explore the mechanism, clinical significance, and management of this potential drug interaction through a review of the supporting evidence.

DATA SOURCES

PubMed, MEDLINE (1946 forward), Embase (1947 forward), PsycINFO (1806 forward), and International Pharmaceutical Abstracts (1970 forward) were searched on February 4, 2017.

STUDY SELECTION AND DATA EXTRACTION

Studies and case reports describing aspects of the potential interaction between MAO-B inhibitors and SSRIs in patients with Parkinson disease and published in English were identified by both title and abstract.

DATA SYNTHESIS

The search identified 8 studies evaluating the potential interaction between SSRIs and the MAO-B inhibitors selegiline and rasagiline. The largest, a retrospective cohort study of 1504 patients with Parkinson disease, found no cases of serotonin syndrome with coadministration of rasagiline and an SSRI. A survey of 63 investigators in the Parkinson Study Group identified 11 potential cases of serotonin syndrome among 4568 patients treated with the combination of selegiline and antidepressants (including SSRIs). In addition, 17 case reports describing the onset of serotonin syndrome with coadministration of an SSRI and either selegiline or rasagiline were identified. Following discontinuation or dose reduction of one or both of the agents, the symptoms of serotonin syndrome gradually resolved in most cases, with none being fatal.

CONCLUSIONS

According to the literature, serotonin syndrome occurs rarely, and the combination of SSRI and MAO-B inhibitor is well tolerated. Therefore, SSRIs and MAO-B inhibitors can be coadministered, provided that their recommended doses are not exceeded and the SSRI dose is kept at the lower end of the therapeutic range. Among the SSRIs, citalopram and sertraline may be preferred.

Safinamide: an add-on treatment for managing Parkinson's disease

Heterogeneous expression of neurotransmitter deficits results from onset and progression of Parkinson's disease. Intervals, characterized by reappearance of motor and associated certain nonmotor symptoms, determine the end of good tolerability and efficacy of oral levodopa therapy. These "OFF" states result from levodopa pharmacokinetics and disease progression-related deterioration of the central buffering capacity for fluctuations of dopamine levels. This review discusses safinamide as an add-on therapeutic agent in orally levodopa-treated patients with "OFF" phenomena. Safinamide provided beneficial effects on "OFF" symptoms in pivotal trials with doses of 50 or 100 mg once daily. Safinamide reversibly inhibits mono-amine oxidase B and declines abnormal glutamate release by modulation of potassium- and sodium ion channels. An ideal candidate for combination with safinamide is opicapone. This inhibitor of peripheral catechol-O-methyltransferase supports continuous brain delivery of levodopa and, thus, the continuous dopaminergic stimulation concept. Both compounds with their once-daily application and good tolerability may complement each other by reduction of necessary oral levodopa intakes and "OFF" times. Thus, a promising, future option will be combination of safinamide and opicapone in one formulation. It will reduce adherence issues and may complement levodopa treatment. It will probably cause less nausea and edema than a dopamine agonist/levodopa regimen.

Serotonin toxicity association with concomitant antidepressants and rasagiline treatment: retrospective study (STACCATO)

BACKGROUND

The serotonin toxicity syndrome (STS) is a potential risk with concurrent use of the monoamine oxidase type-B inhibitor rasagiline and antidepressants.

OBJECTIVE

To assess systematically the occurrence of STS in patients with Parkinson disease (PD) treated with rasagiline plus antidepressants (R+ATD), rasagiline without antidepressants (R), or antidepressants plus anti-PD dopaminergic medications (ATD) other than either rasagiline or selegiline.

METHODS

A phase IV multicenter retrospective cohort study was conducted of patients with PD who began receiving R+ATD, R, or ATD between September 1, 2006, and December 31, 2008. Medical records were reviewed for patient demographics, treatment details, and hospitalizations/emergency department (ED) visits. An adjudication committee independently reviewed records to verify case ascertainment and used the Hunter Serotonin Toxicity Criteria for case definition. Outcome variables were analyzed by descriptive statistics.

RESULTS

A total of 1504 patients with PD (471 with R+ATD; 511 with R; and 525 with ATD) were enrolled from 37 sites. In the R+ATD and ATD groups, selective serotonin reuptake inhibitors (SSRIs) were most frequently used (74.5% and 77%, respectively). In the R+ATD and ATD groups, mean duration of antidepressant use (tricyclic, SSRI, and other) were 50.5-53.5 weeks and 51.7-80.9 weeks, respectively. Overall, 195 patients (13%) from all three groups had one or more hospitalization/ED visits. No cases of STS were identified in any group.

CONCLUSIONS

In this large multicenter retrospective cohort study, concurrent administration of R+ATD was not associated with STS. The findings of this phase IV study expand the drug interaction and pharmacovigilance safety awareness for the use of antidepressants in patients with PD.

Pharmacologic safety concerns in Parkinson's disease: facts and insights

Knowledge and insight of pharmacologic safety issues and drug interactions are important for medical management of Parkinson's disease (PD). This review will discuss several topics, including apomorphine safety and interactions, impulsivity and excessive daytime somnolence associated with dopamine agonists (DAs), tolcapone hepatotoxicity, and monoamine oxidase type-B (MAO-B) inhibitor drug interactions. Initiation of apomorphine requires antiemetic prophylaxis to minimize nausea and orthostatic hypotension. Centrally acting antidopaminergic antiemetics will worsen parkinsonism and block the therapeutic effects of apomorphine and should be avoided. Additionally, serotonin 5-HT(3) receptor antagonist antiemetics should be avoided on the basis of limited clinical data suggesting lack of efficacy for apomorphine-induced nausea. Dopamine-agonist-induced impulsivity and daytime somnolence are not uncommon. When severe, these effects can be disabling and unsafe. Tolcapone-induced hepatotoxicity has been significantly minimized with routine monitoring of liver enzymes, especially during the initial 6 months of therapy. Early detection of abnormal results will allow tolcapone discontinuation before progression to fulminant hepatotoxicity. In patients treated with selective MAO-B inhibitors, the risk of serotonin toxicity (ST) due to a concomitant serotonergic agent (e.g., antidepressants, dextromethorphan, serotonergic analgesics) or hypertensive crisis due to dietary tyramine or sympathomimetic amines appears to be minimal and is based on isolated case reports and overgeneralizations from nonselective MAO inhibitor pharmacology. Concerns about ST or hypertensive crisis should not preclude or restrict clinicians from using MAO-B inhibitors in patients with PD.

Clinically significant drug interactions with newer antidepressants

After the introduction of selective serotonin reuptake inhibitors (SSRIs), other newer antidepressants with different mechanisms of action have been introduced in clinical practice. Because antidepressants are commonly prescribed in combination with other medications used to treat co-morbid psychiatric or somatic disorders, they are likely to be involved in clinically significant drug interactions. This review examines the drug interaction profiles of the following newer antidepressants: escitalopram, venlafaxine, desvenlafaxine, duloxetine, milnacipran, mirtazapine, reboxetine, bupropion, agomelatine and vilazodone. In general, by virtue of a more selective mechanism of action and receptor profile, newer antidepressants carry a relatively low risk for pharmacodynamic drug interactions, at least as compared with first-generation antidepressants, i.e. monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs). On the other hand, they are susceptible to pharmacokinetic drug interactions. All new antidepressants are extensively metabolized in the liver by cytochrome P450 (CYP) isoenzymes, and therefore may be the target of metabolically based drug interactions. Concomitant administration of inhibitors or inducers of the CYP isoenzymes involved in the biotransformation of specific antidepressants may cause changes in their plasma concentrations. However, due to their relatively wide margin of safety, the consequences of such kinetic modifications are usually not clinically relevant. Conversely, some newer antidepressants may cause pharmacokinetic interactions through their ability to inhibit specific CYPs. With regard to this, duloxetine and bupropion are moderate inhibitors of CYP2D6. Therefore, potentially harmful drug interactions may occur when they are coadministered with substrates of these isoforms, especially compounds with a narrow therapeutic index. The other new antidepressants are only weak inhibitors or are not inhibitors of CYP isoforms at usual therapeutic concentrations and are not expected to affect the disposition of concomitantly administered medications. Although drug interactions with newer antidepressants are potentially, but rarely, clinically significant, the use of antidepressants with a more favourable drug interaction profile is advisable. Knowledge of the interaction potential of individual antidepressants is essential for safe prescribing and may help clinicians to predict and eventually avoid certain drug combinations.

Efficacy, safety, and patient preference of monoamine oxidase B inhibitors in the treatment of Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disease and the most treatable. Treatment of PD is symptomatic and generally focuses on the replacement or augmentation of levodopa. A number of options are available for treatment, both in monotherapy of early PD and to treat complications of advanced PD. This review focuses on rasagiline and selegiline, two medications that belong to a class of antiparkinsonian drugs called monoamine oxidase B (MAO-B) inhibitors. Topics covered in the review include mechanism of action, efficacy in early and advanced PD, effects on disability, the controversy regarding disease modification, safety, and patient preference for MAO-B inhibitors.