Efficacy and safety of ketamine for the treatment of depressive symptoms in palliative care: A systematic review

OBJECTIVES

Ketamine has a fast-onset that may offer a paradigm change for depression at end-of-life. We aimed to synthesize evidence regarding the safety and/or efficacy of ketamine in depression treatment within a broad palliative care concept.

METHODS

We searched seven databases and included studies on the safety and efficacy of ketamine for depression treatment in patients diagnosed with any life-threatening disease; further, we conducted a narrative review of the evidence.

RESULTS

Among 2,252 screened titles and abstracts, we included 32 studies in our final synthesis. Specifically, we included 14 case reports, 2 case series, 2 quasi-experimental studies, and 7 randomized clinical trials, as well as data from three unpublished clinical trials and seven cases from four larger case series. Most case reports reported a robust effect; however, the larger studies reported conflicting findings. Five randomized clinical trials reported positive outcomes; however, four of them were focused on a perioperative setting. Further, two negative studies did not primarily focus on depression and did not apply severity cutoffs.

CONCLUSIONS

Although ketamine is generally safe and potentially useful, its efficacy in palliative care settings remains unclear. It may be a reasonable alternative for perioperative depression in oncological patients.

Efficacy and Safety of Subcutaneous Esketamine in the Treatment of Suicidality in Major Depressive Disorder and Bipolar Depression

BACKGROUND AND OBJECTIVE

Affective disorders account for most cases of suicide. The pharmacological arsenal to treat suicidality is limited and available agents take too long to take effect. A large body of evidence shows optimal results of ketamine for treating depression, but the evidence concerning suicidality has not been fully described. We report the first real-world study of severely depressed patients presenting with suicide ideation who were treated with repeated administration of subcutaneous esketamine.

METHODS

We analyzed data from 70 acutely depressed subjects diagnosed with resistant major depressive disorder or bipolar depression. Subjects were administered subcutaneous esketamine once a week for 6 weeks. The primary efficacy endpoint, the change from baseline to 24-h post-administration 6 in the item 10 Montgomery-Åsberg Depression Rating Scale score, was analyzed using a mixed-effects repeated-measures model.

RESULTS

There were significant effects for time on item 10 Montgomery-Åsberg Depression Rating Scale scores (p < 0.0001) but not for a time × diagnosis interaction (p = 0.164) from baseline to the end of the study. Efficacy of esketamine did not differ between groups (major depressive disorder vs bipolar depression) at any timepoint. Statistical significance on suicidality scores was observed from 24 h after the first administration (p < 0.001), and a further reduction was observed with repeated administrations. Esketamine was safe and well tolerated. Mean heart rate remained stable during the administrations and the blood pressure increase was self-limited.

CONCLUSIONS

Repeated subcutaneous esketamine administration had significant anti-suicidality effects in both major depressive disorder and bipolar groups, with a rapid onset of action and a good tolerability profile. Large randomized controlled trials are warranted to confirm these preliminary findings.

The probability of response after each subcutaneous injection of esketamine in treatment-resistant depression

INTRODUCTION

The administration of multiple esketamine doses has shown efficacy for unipolar and bipolar treatment-resistant depression (TRD). Nevertheless, the probability of responding or not after each dose in the real-world remains unknown. This study aimed to estimate it throughout four doses of esketamine, administrated via subcutaneous (SC).

MATERIAL AND METHODS

We conducted a retrospective analysis of a case series of 70 patients with TRD who received treatment from the esketamine assistance program at Federal University of Sao Paulo, between April 2017 and December 2018. The SC injections were administrated weekly at a dose of 0.5-1.0mg/kg, in conjunction with patients' psychotropic drugs. Response was defined as a decrease of at least 50% in the Montgomery-Åsberg Depression Rating Scale between baseline and 24h after dose. We used hidden Markov modeling in order to estimate de probability of response after each esketamine injection.

RESULTS

The probability of a patient that was a "non-responder" to become a "responder" following a SC injection of esketamine was 17.30% and the probability that this patient remains a "non-responder" was 82.70%. The probability of a patient that was a "responder" to remain as a "responder" was 95%.

CONCLUSIONS

Patients with TRD who had not responded after the first dose of esketamine, still had a chance of responding after the subsequent dose administrated via SC.

A Clinical Rationale for Assessing the Impact of Childhood Sexual Abuse on Adjunctive Subcutaneous Esketamine for Treatment-Resistant Depression

Background: A history of child sexual abuse (CSA) is related to higher suicide rates and poor treatment outcomes in depressed adult patients. Twenty years after the first study investigating the effects of ketamine/esketamine on depression and suicide, there is a lack of data on the CSA effects on this emerging treatment. Here, we assess the impact of CSA on adjunctive subcutaneous (SC) esketamine for treatment-resistant depression (TRD). Methods: A directed acyclic graphic (DAG) was designed to identify clinical confounders between CSA and esketamine predictors of response. The confounders were applied in a statistical model to predict depression symptom trajectory in a sample of 67 TRD outpatients. Results: The patient sample had a relatively high prevalence rate of CSA (35.82%). Positive family history of first-degree relatives with alcohol use disorder and sex were clinical mediators of the effects of esketamine in a CSA adult population. Overall, the presence of at least one CSA event was unrelated to esketamine symptom reduction. Conclusions: Unlike responses to conventional antidepressants and psychotherapy, CSA does not appear to predict poor response to esketamine.

Comparative effectiveness of esketamine in the treatment of anhedonia in bipolar and unipolar depression

BACKGROUND

Anhedonia is a symptom associated with poorer outcomes in depression treatment, including resistance to treatment, higher functional impact and suicidality. Few drugs are known to adequately treat anhedonia in both unipolar and bipolar depression. The NMDA antagonist ketamine has been demonstrated to be effective in rapidly ameliorating anhedonia in depressive episodes. The main aim of present study is to evaluate the anti-anhedonic effect of esketamine, the S-enantiomer of ketamine recently approved for treatment-resistant depression, in unipolar and bipolar depression.

METHODS

70 patients with unipolar or bipolar depression were treated with 6 weekly subcutaneous esketamine infusions (0.5-1mg/kg). Anhedonia was measured through MADRS item 8 before and 24h after each infusion.

RESULTS

A significant reduction in anhedonia severity was observed (p<0.0001) after 6 infusions. The effect was statistically significant 24h after the first infusion (p<0.001) in both unipolar and bipolar groups and increased with repeated infusions. Anti-anhedonic effect of esketamine did not differ between groups.

LIMITATIONS

This is an open-label, real-world study. Lack of blinding and of a placebo arm may limit the interpretation of findings.

CONCLUSION

Although preliminary, present findings suggest that repeated subcutaneous esketamine infusions are effective for the treatment of anhedonia in both unipolar and bipolar depressed patients. These results need to be confirmed through replication in larger double-blinded controlled trials.

The probability of response after each subcutaneous injection of esketamine in treatment-resistant depression

INTRODUCTION

The administration of multiple esketamine doses has shown efficacy for unipolar and bipolar treatment-resistant depression (TRD). Nevertheless, the probability of responding or not after each dose in the real-world remains unknown. This study aimed to estimate it throughout four doses of esketamine, administrated via subcutaneous (SC).

MATERIAL AND METHODS

We conducted a retrospective analysis of a case series of 70 patients with TRD who received treatment from the esketamine assistance program at Federal University of Sao Paulo, between April 2017 and December 2018. The SC injections were administrated weekly at a dose of 0.5-1.0mg/kg, in conjunction with patients' psychotropic drugs. Response was defined as a decrease of at least 50% in the Montgomery-Åsberg Depression Rating Scale between baseline and 24h after dose. We used hidden Markov modeling in order to estimate de probability of response after each esketamine injection.

RESULTS

The probability of a patient that was a "non-responder" to become a "responder" following a SC injection of esketamine was 17.30% and the probability that this patient remains a "non-responder" was 82.70%. The probability of a patient that was a "responder" to remain as a "responder" was 95%.

CONCLUSIONS

Patients with TRD who had not responded after the first dose of esketamine, still had a chance of responding after the subsequent dose administrated via SC.

Effects of subcutaneous esketamine on blood pressure and heart rate in treatment-resistant depression

INTRODUCTION AND OBJECTIVES

The impact of multiple subcutaneous (s.c.) esketamine injections on the blood pressure (BP) and heart rate (HR) of patients with unipolar and bipolar treatment-resistant depression (TRD) is poorly understood. This study aimed to assess the cardiovascular safety of multiple s.c. doses of esketamine in patients with TRD.

METHODS

Seventy TRD patients received 394 weekly s.c. esketamine injections in conjunction with oral antidepressant therapy for up to six weeks. Weekly esketamine doses were 0.5, 0.75 or 1.0 mg/kg according to each patient's response to treatment. Participants were monitored before each treatment and every 15 minutes thereafter for 120 minutes. We assessed systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR measurements for the entire treatment course.

RESULTS

BP increased after the first s.c. esketamine injection, reaching maximum mean SBP/DBP levels of 4.87/5.54 mmHg within 30-45 minutes. At the end of monitoring, 120 minutes post dose, vital signs returned to pretreatment levels. We did not detect significant differences in BP between doses of 0.5, 0.75, and 1 mg/kg esketamine. Mean HR did not differ significantly between doses or before and after s.c. esketamine injection.

CONCLUSIONS

The BP changes observed with repeated s.c. esketamine injections were mild and well tolerated for doses up to 1 mg/kg. The s.c. route is a simple and safe method of esketamine administration, even for patients with clinical comorbidities, including obesity, hypertension, diabetes, and dyslipidemia. However, 14/70 patients experienced treatment-emergent transient hypertension (SBP >180 mmHg and/or a DBP >110 mmHg). Therefore, we strongly recommend monitoring BP for 90 minutes after esketamine dosing. Since s.c. esketamine is cheap, requires less frequent dosing (once a week), and is a simpler procedure compared to intravenous infusions, it might have an impact on public health.

Repeated subcutaneous esketamine administration for depressive symptoms and pain relief in a terminally ill cancer patient: A case report

BACKGROUND

Depressive disorders are common among cancer patients. Ketamine can quickly relieve depression, and its subcutaneous administration appears to be as effective as and probably safer than its standard intravenous administration. Herein, we report a case verifying the antidepressant effect of a subcutaneous esketamine formulation.

CASE PRESENTATION

A 65-year-old male with metastatic abdominal tumor reported sadness, weight loss, fatigue, hopelessness, insomnia, inattention, and reduced motivation. His scores on the visual analogical scale for pain and Montgomery-Asberg depression rating scale were 8/10 and 30/60, respectively.

POSSIBLE COURSES OF ACTION

Monoaminergic antidepressants are effective, but their response is slow for end-of-life care.

FORMULATION OF A PLAN

Esketamine was preferred because it possibly contributes to pain relief. It can repeatedly be infused intravenously, but was subcutaneously administered twice a week for safety reasons.

OUTCOME

The patient showed continuous mood improvement, achieving depression remission on day 7. Pain relief was observed but without stability. His vital signs remained stable, and he remained calm, without major complaints.

LESSONS FROM THE CASE

Repeated subcutaneous esketamine injections are possibly safe and effective in pain and depression relief in palliative care cancer patients.

VIEW ON RESEARCH PROBLEMS, OBJECTIVES, OR QUESTIONS GENERATED BY THE CASE

Placebo-controlled studies with similar cases are needed to establish efficacy and safety.