Impact of immunosuppressive agents on the management of immune-related adverse events of immune checkpoint blockers

BACKGROUND

Immune checkpoint blockers (ICBs) can induce immune-related adverse events (irAEs) whose management is based on expert opinion and may require the prescription of steroids and/or immunosuppressants (ISs). Recent data suggest that these treatments can reduce the effectiveness of ICBs.

OBJECTIVE

To investigate the relationship between the use of steroids and/or ISs and overall survival (OS) and progression-free survival (PFS) among ICB-treated patients with an irAE.

METHODS

We prospectively collected data from the medical records of patients with solid tumors or lymphoma in the French REISAMIC cohort and who had been treated with ICBs between June 2014 and June 2020.

RESULTS

184 ICB-treated patients experienced at least one Common Terminology Criteria for Adverse Events grade ≥ 2 irAE. 107 (58.2%) were treated with steroids alone, 20 (10.9%) with steroids plus IS, 57 (31.0%) not received steroids or IS. The median OS was significantly shorter for patients treated with steroids alone (25.2 months [95% confidence interval (CI): 22.3-32.4] than for patients treated without steroids or IS (63 months [95%CI: 40.4-NA]) and those receiving an IS with steroids (53.4 months [95%CI: 47.3-NA]) (p < 0.001). The median PFS was significantly shorter for patients treated with steroids alone (17.0 months [95%CI: 11.7-22.9]) than for patients treated without steroids or IS (33.9 months [95%CI: 18.0-NA]) and those receiving an IS with steroids (41.1 months [95%CI: 26.2-NA]) (p = 0.006). There were no significant intergroup differences in the hospital admission and infection rates.

CONCLUSION

In a prospective cohort of ICB-treated patients, the use of IS was not associated with worse OS or PFS, contrasting with the use of steroids for the management of irAEs.

Efficacy and safety of immune checkpoint inhibitor rechallenge in individuals with hepatocellular carcinoma

Background & Aims

We investigated the efficacy and safety of immune checkpoint inhibitor (ICI) rechallenge in patients with hepatocellular carcinoma (HCC) who received ICI-based therapies in a previous systemic line.

Methods

In this international, retrospective multicenter study, patients with HCC who received at least two lines of ICI-based therapies (ICI-1, ICI-2) at 14 institutions were eligible. The main outcomes included best overall response and treatment-related adverse events.

Results

Of 994 ICI-treated patients screened, a total of 58 patients (male, n = 41; 71%) with a mean age of 65.0±9.0 years were included. Median systemic treatment lines of ICI-1 and ICI-2 were 1 (range, 1-4) and 3 (range, 2-9), respectively. ICI-based therapies used at ICI-1 and ICI-2 included ICI alone (ICI-1, n = 26, 45%; ICI-2, n = 4, 7%), dual ICI regimens (n = 1, 2%; n = 12, 21%), or ICI combined with targeted therapies/anti-VEGF (n = 31, 53%; n = 42, 72%). Most patients discontinued ICI-1 due to progression (n = 52, 90%). Objective response rate was 22% at ICI-1 and 26% at ICI-2. Responses at ICI-2 were also seen in patients who had progressive disease as best overall response at ICI-1 (n = 11/21; 52%). Median time-to-progression at ICI-1 and ICI-2 was 5.4 (95% CI 3.0-7.7) months and 5.2 (95% CI 3.3-7.0) months, respectively. Treatment-related adverse events of grade 3-4 at ICI-1 and ICI-2 were observed in 9 (16%) and 10 (17%) patients, respectively.

Conclusions

ICI rechallenge was safe and resulted in a treatment benefit in a meaningful proportion of patients with HCC. These data provide a rationale for investigating ICI-based regimens in patients who progressed on first-line immunotherapy in prospective trials.

Impact and implications

Therapeutic sequencing after first-line immune checkpoint inhibitor (ICI)-based therapy for advanced hepatocellular carcinoma (HCC) remains a challenge as no available second-line treatment options have been studied in immunotherapy-pretreated patients. Particularly, the role of ICI rechallenge in patients with HCC is unclear, as data from prospective trials are lacking. We investigated the efficacy and safety of ICI-based regimens in patients with HCC pretreated with immunotherapy in a retrospective, international, multicenter study. Our data provide the rationale for prospective trials investigating the role of ICI-based regimens in patients who have progressed on first-line immunotherapy.

Breast cancer immunotherapy: Current and novel approaches

The crucial role of the immune system in the progression/regression of breast cancer (BC) should always be taken into account. Various immunotherapy approaches have been investigated for BC, including tumor-targeting antibodies (bispecific antibodies), adoptive T cell therapy, vaccines, and immune checkpoint blockade such as anti-PD-1. In addition, a combination of conventional chemotherapy and immunotherapy approaches contributes to improving patients' overall survival rates. Although encouraging outcomes have been reported in most clinical trials of immunotherapy, some obstacles should still be resolved in this regard. Recently, personalized immunotherapy has been proposed as a potential complementary medicine with immunotherapy and chemotherapy for overcoming BC. Accordingly, this review discusses the brief association of these methods and future directions in BC immunotherapy.

Therapeutic Development of Immune Checkpoint Inhibitors

Immune checkpoint blockade (ICB) has been proven to be an effective strategy for enhancing the effector activity of anti-tumor T cells, and checkpoint blockers targeting CTLA-4, PD-1, and PD-L1 have displayed strong and durable clinical responses in certain cancer patients. The new hope brought by ICB therapy has led to the boost in therapeutic development of ICBs in recent years. Nonetheless, the therapeutic efficacy of ICBs varies substantially among cancer types and patients, and only a proportion of cancer patients could benefit from ICBs. The emerging targets and molecules for enhancing anticancer immunity may bring additional therapeutic opportunities for cancer patients. The current challenges in the ICB therapy have been discussed, aimed to provide further strategies for maximizing the efficacy of ICB therapy.

Clinical Outcomes of Immune Checkpoint Blocker Therapy for Malignant Melanoma in Korean Patients: Potential Clinical Implications for a Combination Strategy Involving Radiotherapy

PURPOSE

We investigated the clinical efficacy of immune checkpoint blocker (ICB) therapy for metastatic or advanced melanoma in Korean patients. As well, we assessed whether the effects of ICBs can be enhanced by combination therapy with palliative radiotherapy (RT).

Materials and Methods

We retrospectively reviewed the records of 127 patients with metastatic melanoma who received ICB with or without palliative RT between 2014 and 2018. The melanoma subtypes were classified as follows: chronic sun-damaged (CSD), acral, mucosal, and uveal. The primary endpoint was the objective response rate (ORR).

RESULTS

The overall ORR was 15%, with 11 complete and eight partial responses. ORRs for CSD, acral/mucosal, and uveal melanomas were 50%, 16.5%, and 0%, respectively (p=0.009). In addition to the subtype, stage at treatment, total tumor burden at treatment, and ICB type were significantly associated with ORR (all p < 0.05). Palliative RT was administered in 44% of patients during the treatment, and it did not affect ORR. Clinical responders to ICB therapy exhibited significantly higher 1-year progression-free and overall survival rates than nonresponders.

CONCLUSION

ORR for ICB monotherapy in Korean patients with melanoma is relatively modest compared with that in Western patients because the non-CSD subtypes are predominant in the Korean population. Our findings regarding combination therapy with ICB provided a rationale for the initiation of our phase II study (NCT04017897).

Predicting response to pembrolizumab in metastatic melanoma by a new personalization algorithm

BACKGROUND

At present, immune checkpoint inhibitors, such as pembrolizumab, are widely used in the therapy of advanced non-resectable melanoma, as they induce more durable responses than other available treatments. However, the overall response rate does not exceed 50% and, considering the high costs and low life expectancy of nonresponding patients, there is a need to select potential responders before therapy. Our aim was to develop a new personalization algorithm which could be beneficial in the clinical setting for predicting time to disease progression under pembrolizumab treatment.

METHODS

We developed a simple mathematical model for the interactions of an advanced melanoma tumor with both the immune system and the immunotherapy drug, pembrolizumab. We implemented the model in an algorithm which, in conjunction with clinical pretreatment data, enables prediction of the personal patient response to the drug. To develop the algorithm, we retrospectively collected clinical data of 54 patients with advanced melanoma, who had been treated by pembrolizumab, and correlated personal pretreatment measurements to the mathematical model parameters. Using the algorithm together with the longitudinal tumor burden of each patient, we identified the personal mathematical models, and simulated them to predict the patient's time to progression. We validated the prediction capacity of the algorithm by the Leave-One-Out cross-validation methodology.

RESULTS

Among the analyzed clinical parameters, the baseline tumor load, the Breslow tumor thickness, and the status of nodular melanoma were significantly correlated with the activation rate of CD8+ T cells and the net tumor growth rate. Using the measurements of these correlates to personalize the mathematical model, we predicted the time to progression of individual patients (Cohen's κ = 0.489). Comparison of the predicted and the clinical time to progression in patients progressing during the follow-up period showed moderate accuracy (R² = 0.505).

CONCLUSIONS

Our results show for the first time that a relatively simple mathematical mechanistic model, implemented in a personalization algorithm, can be personalized by clinical data, evaluated before immunotherapy onset. The algorithm, currently yielding moderately accurate predictions of individual patients' response to pembrolizumab, can be improved by training on a larger number of patients. Algorithm validation by an independent clinical dataset will enable its use as a tool for treatment personalization.