Efficacy and safety of anti-PD-1/PD-L1-based dual immunotherapies versus PD-1/PD-L1 inhibitor alone in patients with advanced solid tumor: a systematic review and meta-analysis.

INTRODUCTION: Numerous randomized controlled trials (RCTs) have investigated PD-1/PD-L1 inhibitor-based combination therapies. The debate surrounding the potential additive clinical benefits of combination of two immune-oncology (IO) therapies for cancer patients persists. METHODS: Both published and grey sources of randomized clinical trials that compared anti-PD-1/PD-L1-based immunotherapy combinations with monotherapy in patients with advanced or metastatic solid tumors were encompassed. The primary outcome was progression-free survival (PFS), and secondary outcomes included objective response rate (ORR), overall survival (OS) and treatment-related adverse events (TRAEs). RESULTS: Our analysis encompassed 31 studies comprising 10,341 patients, which covered 12 distinct immune-oncology combination regimens. Across all patients, the immunotherapy combinations exhibited the capability to enhance the ORR (OR = 1.23 [95% CI 1.13-1.34]) and extend PFS (HR = 0.91 [95% CI 0.87-0.95]). However, the observed enhancement in OS (HR = 0.96 [95% CI 0.91-1.01]) was of no significance. Greater benefits in terms of PFS (HR = 0.82 [95% CI 0.72 to 0.93]) and OS (HR = 0.85 [95% CI 0.73 to 0.99]) may be particularly pronounced in cases where PD-L1 expression is negative. Notably, despite a heightened risk of any-grade TRAEs (OR = 1.72 [95% CI 1.40-2.11]) and grade greater than or equal to 3 TRAEs (OR = 2.01 [95% CI 1.67-2.43]), toxicity was generally manageable. CONCLUSIONS: This study suggests that incorporating an additional immunotherapy agent with PD-1/PD-L1 inhibitors can elevate the response rate and reduce the risk of disease progression, all while maintaining manageable toxicity. However, there remains a challenge in translating these primary clinical benefits into extended overall survival.

Clinical outcomes of immune checkpoint inhibitor combined with other targeted or immunological therapy regimens for the treatment of advanced bile tract cancer: a systematic review and meta-analysis.

Background and aims: A single immune checkpoint inhibitor (ICI) regimen has limited value in treating advanced bile tract cancer (BTC); therefore, ICI combination therapy is often applied. This meta-analysis aimed to evaluate the effectiveness and safety of ICI combination therapy for advanced BTC. Methods: The study protocol was registered on PROSPERO (CRD42023452422). Data on the median progression-free survival (PFS), median overall survival (OS), objective response rate (ORR), disease control rate (DCR), and grade ≥3 adverse events (AEs) reported in relevant studies were pooled and analyzed to determine the efficacy and safety of ICI combination therapy. Results: In total, 15 studies with 665 patients were included in this meta-analysis. The overall ORR and DCR were 34.6% and 77.6%, respectively. The overall median PFS and OS were 6.06 months [95% confidence interval (CI): 4.91-7.21] and 12.11 months (95% CI: 10.66-13.55), respectively. Patients receiving ICI combination therapy in addition to other therapies had a considerably prolonged median PFS and OS (z=9.69, p<0.001 and z=16.17, p<0.001). Patients treated as first-line treatment had a substantially longer median PFS and OS compared to patients treated as non-first-line treatment (z=11.19, p<0.001 and z=49.17, p<0.001). The overall pooled grade ≥3 AEs rate was 38.2% (95% CI: 0.268-0.497) and was not influenced by whether ICI therapy was combined with other treatments or not or the treatment line. Conclusion: Advanced BTC patients may benefit from ICI combination treatment without additional AEs. However, concurrent chemotherapy or radiotherapy is still needed to achieve better outcomes. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023452422.

The efficacy and safety of neoadjuvant chemoradiotherapy combined with immunotherapy for locally advanced rectal cancer patients: a systematic review.

Background: Several studies have explored the effectiveness of PD-1/PD-L1 inhibitors combined with neoadjuvant chemoradiotherapy (nCRT) in the treatment of locally advanced rectal cancer(LARC), particularly in microsatellite stable(MSS) or mismatch repair proficient(pMMR) LARC patients. We undertook a single-arm systematic review to comprehensively evaluate the advantages and potential risks associated with the use of PD-1/PD-L1 inhibitors in conjunction with nCRT for patients diagnosed with locally advanced rectal cancer. Methods: The PubMed, Embase, Cochrane Library, ClinicalTrials.gov, ASCO and ESMO were searched for related studies. The main outcomes were pathologic complete response (pCR), major pathological response (MPR), anal preservation, and adverse effects (AEs). Results: Fourteen articles including 533 locally advanced rectal cancer (LARC) patients were analyzed. The pooled pCR, MPR, and anal preservation rates were 36%, 66% and 86%. Grade ≥3 adverse events occurred in 20%. Subgroup analysis showed that; dMMR/MSI-H had a pooled pCR (100%) and MPR (100%), pMMR/MSS had a pooled pCR (38%) and MPR (60%); the short-course radiotherapy and long-course radiotherapy had pooled pCR rates of 51% and 30%, respectively. The rates of pCR for the concurrent and sequential immuno-chemoradiotherapy subgroups at 30% and 40%, mirroring pCR rates for the PD-L1 and PD-1 inhibitor subgroups were 32% and 40%, respectively. Conclusion: In cases of locally advanced rectal cancer, PD-1/PD-L1 inhibitors combined with neoadjuvant chemoradiotherapy have shown promising response rates and acceptable toxicity profiles. PD-1/PD-L1 inhibitors combined with neoadjuvant chemoradiotherapy hence has a positive outcome even in MSS LARC patients. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/#myprospero, identifier CRD42023465380.

Toxicity of immunotherapy combinations with chemotherapy across tumor indications: Current knowledge and practical recommendations.

Chemotherapy associated with Immune Checkpoint Inhibitors is currently the standard of care in several tumor indications. This combination approach improves progression free survival (PFS), overall survival (OS) and complete pathological response (pCR) in several cancer types both in the early and metastatic approaches. However, the distinct spectrum of toxicities between cytotoxic side effects and immune related adverse events (irAEs) with similar clinical presentations and different management strategies remains a challenge in daily practice for healthcare professionals. This review summarizes the most common toxicities reported in the randomized clinical trials that led to the subsequent FDA approval of these combinations, across tumor indications. We cite in particular: non-small cell lung cancer, small cell lung cancer, triple negative breast cancer, squamous cell carcinoma of the head and neck, gastric carcinoma, esophageal carcinoma, cervical carcinoma and biliary tract carcinoma. We found that the combination of chemotherapy and immunotherapy was associated with an increased incidence of all grade adverse events (RR 1.11 [1.09; 1.12]) without an excess in treatment related mortality when compared to chemotherapy alone. We report also an increase in the incidence of serious adverse events (grade ≥ 3) (RR 1.16 [1.10;1.24]); in particular: high grade diarrhea, dyspnea, fatigue, rash and elevated liver enzymes. Together with the collaboration of our institutional network of organ specialists with expertise in irAEs, we propose practical recommendations for physicians to enhance clinical care and management of patients undergoing treatment with combined ICI immunotherapy and chemotherapy.

Efficacy and safety of transarterial chemoembolization combined with targeted therapy and immunotherapy versus with targeted monotherapy in unresectable hepatocellular carcinoma: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: The application of transarterial chemoembolization (TACE) in combination with targeted therapy and immunotherapy (TACE-T-I) for unresectable hepatocellular carcinoma (HCC) has gained increasing attention. However, there are variations in the efficacy and safety outcomes between TACE-T-I versus TACE combined with targeted drugs (TACE-T). This study aims to systematically evaluate the efficacy and safety of TACE-T-I versus TACE-T in unresectable HCC. METHODS: PubMed, Embase, Cochrane Library, and Web of Science databases were searched from inception to August 21, 2023, for comparative studies on TACE-T-I versus TACE-T for unresectable HCC. Outcome measures included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR) and the incidence of treatment-related adverse events (TRAEs). OS was the primary outcome of this study. Weighted mean difference (WMD) or hazard ratio (HR) was used as the pooled statistic for OS and PFS. Relative risk (RR) was employed as the pooled statistic for ORR, DCR and the incidence of TRAEs. And 95% confidence intervals (CIs) were calculated for all effect measures. Data analysis was conducted using Stata 14.0 software. RESULTS: The meta-analysis included 14 studies with 2144 patients. The pooled results showed that compared with patients in the TACE-T group, patients in the TACE-T-I group had higher ORR (RR = 1.61; 95%CI: 1.38-1.89) and DCR (RR = 1.17; 95%CI: 1.09-1.26). Patients in the TACE-T-I group experienced prolonged PFS (WMD = 3.08; 95%CI: 2.63-3.53) and OS (WMD = 5.76; 95%CI: 4.68-6.84). And the risk of disease progression (HR = 0.45; 95%CI: 0.37-0.55) and death (HR = 0.43; 95%CI: 0.38-0.49) was lower in the TACE-T-I group. Common TRAEs included fever, pain, abdominal pain, nausea, vomiting, elevated ALT, elevated AST, hypertension, hand-foot syndrome, proteinuria, and diarrhea. The incidence and severity of TRAEs in the TACE-T-I group were similar to those in the TACE-T group, with no significant differences (P > .05). CONCLUSION: Current evidence suggests that, on the basis of TACE combined with targeted therapy, the addition of immunotherapy provides better clinical efficacy and survival benefits for unresectable HCC patients, with good tolerability.

Highly variable timing renders immunotherapy efficacy and toxicity impractical biomarkers of one another in clinical practice.

Background: A useful clinical biomarker requires not only association but also a consistent temporal relationship. For instance, chemotherapy-induced neutropenia and epidermal growth-factor inhibitor-related acneiform rash both occur within weeks of treatment initiation, thereby providing information prior to efficacy assessment. Although immune checkpoint inhibitor (ICI)-associated immune-related adverse events (irAE) have been associated with therapeutic benefit, irAE may have delayed and highly variable onset. To determine whether ICI efficacy and irAE could serve as clinically useful biomarkers for predicting each other, we determined the temporal relationship between initial efficacy assessment and irAE onset in a diverse population treated with ICI. Methods: Using two-sided Fisher exact and Cochran-Armitage tests, we determined the relative timing of initial efficacy assessment and irAE occurrence in a cohort of 155 ICI-treated patients (median age 68 years, 40% women). Results: Initial efficacy assessment was performed a median of 50 days [interquartile range (IQR) 39-59 days] after ICI initiation; median time to any irAE was 77 days (IQR 28-145 days) after ICI initiation. Median time to first irAE was 42 days (IQR 20-88 days). Overall, 58% of any irAE and 47% of first irAE occurred after initial efficacy assessment. For clinically significant (grade ≥2) irAE, 60% of any and 53% of first occurred after initial efficacy assessment. The likelihood of any future irAE did not differ according to response (45% for complete or partial response vs. 47% for other cases; P=1). In landmark analyses controlling for clinical and toxicity follow-up, patients demonstrating greater tumor shrinkage at initial efficacy assessment were more likely to develop future grade ≥2 (P=0.05) and multi-organ (P=0.02) irAE. Conclusions: In contrast to that seen with chemotherapy and molecularly targeted therapies, the temporal relationship between ICI efficacy and toxicity is complex and bidirectional. In practice, neither parameter can be routinely relied on as a clinical biomarker to predict the other.

Comparison of neoadjuvant chemotherapy or chemoradiotherapy plus immunotherapy for locally resectable esophageal squamous cell carcinoma.

Background: Neoadjuvant chemotherapy plus immunotherapy (nCT + ICIs) and neoadjuvant chemoradiotherapy plus immunotherapy (nCRT + ICIs) both induced favorable pathological response and tolerant toxicities for locally resectable esophageal squamous cell carcinoma (ESCC). However, few studies compared safety and efficacy between the two treatment strategies. Methods: This retrospective study collected clinical data of locally resectable ESCC patients who underwent nCT + ICIs or nCRT + ICIs followed by esophagectomy from November 2019 to December 2022. The incidence of adverse events, surgical outcomes, short and long-term efficacy, and treatment costs were compared. Results: A total of 206 patients were included, with a ratio of 158:48 between nCT + ICIs group and nCRT + ICIs group. The two groups exhibited well-balanced baseline characteristics. Most adverse events were grade 1-2 in both groups. The nCT + ICIs group had a longer operative time (334.00 ± 170.2 min vs 279.60 ± 88.31 min, P=0.020) than nCRT + ICIs group, but there were no differences in surgical complications. Although nCT + ICIs group had a lower pCR rate (32.3% vs 52.1%, P=0.004), the 2-year overall survival (84.42% vs 81.70%, P=0.860), 2-year disease-free survival (83.21% vs 80.47%, P=0.839), and recurrence patterns were similar to nCRT + ICIs group. In addition, nCT + ICIs group had significantly lower expenses (188796.00 ± 107704.00 RMB vs 231808.00 ± 48067.00 RMB, P=0.045). Conclusion: Overall, nCT + ICIs have comparable safety and efficacy compared to nCRT + ICIs for locally resectable ESCC, but with lower hospitalization costs.

Case report: Fatal overwhelming post-splenectomy infection in a patient with metastatic angiosarcoma treated with immunotherapy.

A patient in his 40s with splenic angiosarcoma metastatic to the liver underwent splenectomy, chemotherapy, and partial hepatectomy before being treated on a clinical trial with CTLA4 and PD1 inhibitors. He had received pneumococcal and meningococcal vaccines post-splenectomy. On week 10, he developed grade 3 immune-related colitis, successfully treated with the anti-tumor necrosis factor-alpha inhibitor infliximab and steroids. After 4 cycles of treatment, scans showed partial response. He resumed anti-PD1 therapy, and 6 hours after the second dose of anti-PD1 he presented to the emergency room with hematemesis, hematochezia, hypotension, fever, and oxygen desaturation. Laboratory tests demonstrated acute renal failure and septicemia (Streptococcus pneumoniae). He died 12 hours after the anti-PD1 infusion from overwhelming post-splenectomy infection (OPSI). Autopsy demonstrated non-viable liver tumors among other findings. In conclusion, patients undergoing immunotherapy and with prior history of asplenia should be monitored closely for OPSI as they may be at increased risk.

Efficacy and safety of targeted therapy plus immunotherapy combined with hepatic artery infusion chemotherapy (FOLFOX) for unresectable hepatocarcinoma.

BACKGROUND: The advent of cutting-edge systemic therapies has driven advances in the treatment of hepatocellular carcinoma (HCC), and therapeutic strategies with multiple modes of delivery have been shown to be more efficacious than monotherapy. However, the mechanisms underlying this innovative treatment modality have not been elucidated. AIM: To evaluate the clinical efficacy of targeted therapy plus immunotherapy combined with hepatic arterial infusion chemotherapy (HAIC) of FOLFOX in patients with unresectable HCC. METHODS: We enrolled 53 patients with unresectable HCC who received a combination of targeted therapy, immunotherapy, and HAIC of FOLFOX between December 2020 and June 2021 and assessed the efficacy and safety of the treatment regimen. RESULTS: The objective response rate was 60.4% (32/53), complete response was 24.5% (13/53), partial response was 35.9% (19/53), and stable disease was 39.6% (21/53). The median duration of response and median progression-free survival were 9.1 and 13.9 months, respectively. The surgical conversion rate was 34.0% (18/53), and 1-year overall survival was 83.0% without critical complicating diseases or adverse events (AEs). CONCLUSION: The regimen of HAIC of FOLFOX, targeted therapy, and immunotherapy was curative for patients with unresectable HCC, with no serious AEs and a high rate of surgical conversion.

Drug-induced Lung Disease in the Oncology Patient: From Cytotoxic Agents to Immunotherapy.

Drug-induced lung disease is commonly encountered, especially in the oncology setting. Diagnosis is challenging because clinical and radiologic findings are nonspecific, often overlapping with other lung pathologies in these patients due to underlying neoplasia, infection, or other treatment effects such as radiotherapy. Furthermore, oncology patients often receive multiple antineoplastic agents concurrently, and virtually every agent has an association with lung injury. In this article, we will review a variety of antineoplastic agents that are associated with drug-induced injury and discuss incidence, their typical timing of onset, and imaging features.

Toxicity in Older Patients with Cancer Receiving Immunotherapy: An Observational Study.

BACKGROUND: Checkpoint inhibition has emerged as an effective treatment strategy for a variety of cancers, including in older adults. However, older patients with cancer represent a heterogenous group as they can vary widely in frailty, cognition, and physical status. OBJECTIVE: This study aims to investigate the association between clinical frailty and immune-related treatment toxicity, hospitalization, and treatment discontinuation due to immune-related treatment toxicity in older patients treated with checkpoint inhibitors. METHODS: Patients aged 70 years and older treated with checkpoint inhibitors were selected from the TENT study, IMAGINE study, and "Tolerability and safety of immunotherapy study". Clinical frailty was assessed by the Geriatric-8 test score and World Health Organization (WHO) status. Outcomes were grades 3-5 toxicity, hospitalization, and treatment discontinuation due to toxicity during treatment. RESULTS: Of 99 patients included, 22% had comorbidities. While 33% of the patients were considered frail based on an abnormal Geriatric-8 test score of < 15, physical impairments were considered absent in 51% (WHO score of 0) and mild in 40% (WHO score of 1). Despite the limited sample size of the cohort, consistent trends were observed with patients with an abnormal Geriatric-8 test score of < 15 or a higher WHO score of 1 for having higher odds of toxicity [odds ratio (OR) 2.32 (95% CI 0.41-13.02); OR 1.33 (95% CI 0.45-4.17)], treatment discontinuation due to immune-related treatment toxicity [OR 2.25 (95% CI 0.61-8.31); OR 2.18 (95% CI 0.7-6.73)], and hospitalization due to immune-related treatment toxicity [OR 3.72 (95% CI 0.39-35.4); OR 1.31 (95% CI 0.35-4.9)]. Moreover, in a sub-analysis, we observed that the treatment discontinuation due to immune-related treatment toxicity occurred often in patients with grade 1-2 toxicity as well. CONCLUSIONS: Although not statistically significant, in older patients treated with immunotherapy in a real-life population with cancer, we observed consistent trends towards increased toxicity, hospitalization, and treatment discontinuation with increasing frailty. Larger studies are needed to confirm these exploratory results. Moreover, older patients with a lower toxicity grade 1-2 experienced early treatment discontinuation frequently, suggesting a lower tolerance of toxicity.

Use of artificial intelligence chatbots in clinical management of immune-related adverse events.

BACKGROUND: Artificial intelligence (AI) chatbots have become a major source of general and medical information, though their accuracy and completeness are still being assessed. Their utility to answer questions surrounding immune-related adverse events (irAEs), common and potentially dangerous toxicities from cancer immunotherapy, are not well defined. METHODS: We developed 50 distinct questions with answers in available guidelines surrounding 10 irAE categories and queried two AI chatbots (ChatGPT and Bard), along with an additional 20 patient-specific scenarios. Experts in irAE management scored answers for accuracy and completion using a Likert scale ranging from 1 (least accurate/complete) to 4 (most accurate/complete). Answers across categories and across engines were compared. RESULTS: Overall, both engines scored highly for accuracy (mean scores for ChatGPT and Bard were 3.87 vs 3.5, p<0.01) and completeness (3.83 vs 3.46, p<0.01). Scores of 1-2 (completely or mostly inaccurate or incomplete) were particularly rare for ChatGPT (6/800 answer-ratings, 0.75%). Of the 50 questions, all eight physician raters gave ChatGPT a rating of 4 (fully accurate or complete) for 22 questions (for accuracy) and 16 questions (for completeness). In the 20 patient scenarios, the average accuracy score was 3.725 (median 4) and the average completeness was 3.61 (median 4). CONCLUSIONS: AI chatbots provided largely accurate and complete information regarding irAEs, and wildly inaccurate information ("hallucinations") was uncommon. However, until accuracy and completeness increases further, appropriate guidelines remain the gold standard to follow.

[Drug-related exanthema under immunotherapy and targeted oncological therapy]. / Arzneimittelexantheme unter Immun- und zielgerichteter onkologischer Therapie.

BACKGROUND: Oncological therapies can cause a variety of mucocutaneous adverse events. Exanthematous adverse events can be challenging in the context of the urgent need for cancer treatment due to their spread, sometimes rapid progression, and mucous membrane or organ involvement. MATERIALS AND METHODS: This article provides an overview of the most important exanthematic dermatoses as side effects of modern drug-based tumor therapies with diagnostic and therapeutic information for clinicians, taking into account the current literature and guidelines. RESULTS: Exanthematous adverse events of immune checkpoint inhibitors, EGFR antagonists, kinase inhibitors, bispecific T­cell engagers, and the CCR4 inhibitor mogamulizumab are reviewed in detail. CONCLUSIONS: Cutaneous side effects are common across all drug classes and cover a broad spectrum. While some adverse events are specific to one drug class, many exanthemas can occur with both oncological immunotherapies and various targeted therapies. A reliable diagnosis, dose adjustment or discontinuation of the offending agent in consultation with the treating oncologists and appropriate symptomatic therapy are important for correct management. In the case of severe, life-threatening drug reactions, however, permanent discontinuation of the drug is essential.

The fibrosis-4 index is a prognostic factor for cholangiocarcinoma patients who received immunotherapy.

Background: Research of immunotherapy for cholangiocarcinoma has yielded some results, but more clinical data are needed to prove its efficacy and safety. Moreover, there is a need to identify accessible indexes for selecting patients who may benefit from such treatments. Methods: The medical records of 66 cholangiocarcinoma patients who underwent immunotherapy were retrospectively collected. The effectiveness of immunotherapy was assessed by tumor response, progression-free survival (PFS), and overall survival (OS), while safety was evaluated by adverse events during treatment. Univariate and multivariate Cox regression analyses were performed to identify prognostic risk factors for PFS and OS, and Kaplan-Meier curves of potential prognostic factors were drawn. Results: Overall, in this study, immunotherapy achieved an objective response rate of 24.2% and a disease control rate of 89.4% for the included patients. The median PFS was 445 days, and the median OS was 772.5 days. Of the 66 patients, 65 experienced adverse events during treatment, but none had severe consequences. Multivariate Cox analysis indicated that tumor number is a prognostic risk factor for disease progression following immunotherapy in cholangiocarcinoma patients, while tumor differentiation and the fibrosis-4 (FIB-4) index are independent risk factors for OS. Conclusion: In general, immunotherapy for cholangiocarcinoma is safe, with adverse events remaining within manageable limits, and it can effectively control disease progression in most patients. The FIB-4 index may reflect the potential benefit of immunotherapy for patients with cholangiocarcinoma.

Case report: Is severe toxicity the price to pay for high sensitivity to checkpoint inhibitors immunotherapy in desmoplastic melanoma?

Background: Desmoplastic melanoma (DM) is a rare subtype of melanoma characterized by high immunogenicity which makes it particularly suitable for immune checkpoint inhibitors (ICIs) treatment. Case presentation: We report the case of a 53-year-old man with metastatic DM successfully treated with the combination of anti-CTLA-4 and anti-PD-1 antibodies, who developed serious immune-related adverse events (irAEs). The primary tumor was characterized by absent PD-L1 expression and no-brisk lymphocytes infiltration. NGS showed absence of BRAF mutation, a high tumor mutational burden, and an UV-induced DNA damage signature. Metastatic lesions regressed rapidly after few cycles of ICIs until complete response, however the patient developed serious irAEs including hypothyroidism, adrenal deficiency, and acute interstitial nephritis which led to the definitive suspension of treatment. Currently, the patient has normal renal functionality and no disease relapse after 26 months from starting immunotherapy, and after 9 months from its definitive suspension. Conclusion: Efficacy and toxicity are two sides of the same coin of high sensitivity to ICIs in DM. For this reason, these patients should be closely monitored during ICIs therapy to promptly identify serious side effects and to correctly manage them.

Immunotherapy Toxicity Management in Clinical Practice: Building the Clinical Infrastructure for Immune-related Adverse Event Evaluation and Care.

Cancer immunotherapy is revolutionary for survival but has complications due to immunogenicity with unpredictable and potentially long-lasting autoimmune side effects known as immune-related adverse events (irAEs). Currently, treatment beyond corticosteroids can be complicated by the diversity of providers who are needed across a variety of clinical settings to manage irAEs. We outline the role of critical players in the management of irAEs, discuss the current limitations that exist, and propose various methodologies that can be adapted across clinical settings to tackle these needs. We aim to better understand who can be affected by irAEs and tailor diagnostics and therapeutics appropriately.

Anti-PD-1 antibody in combination with radiotherapy as first-line therapy for unresectable intrahepatic cholangiocarcinoma.

BACKGROUND: Unresectable intrahepatic cholangiocarcinoma (iCCA) has a poor prognosis despite treatment with standard combination chemotherapy. We aimed to evaluate the efficacy and safety of radiotherapy in combination with an anti-PD-1 antibody in unresectable iCCA without distant metastases. METHODS: In this phase II study, patients with histopathologically confirmed unresectable primary or postoperative recurrent iCCA without distant metastases were enrolled. Patients received external radiotherapy with a dose of ≥45 Gy (2-2.5 Gy per fraction), followed by anti-PD-1 immunotherapy (camrelizumab 200 mg once, every 3 weeks) initiated within 7 days after completion of radiotherapy as first-line therapy. The primary endpoint was 1-year progression-free survival (PFS) rate. The secondary end points included safety, objective response rate (ORR), disease control rate (DCR), and overall survival (OS). RESULTS: From December 2019 to March 2021, 36 patients completed radiotherapy and at least one cycle of immunotherapy and were included in efficacy and safety analyses. The median follow-up was 19.0 months (IQR 12.0-24.0), and the one-year PFS rate was 44.4% (95% CI, 30.8-64.0). The median PFS was 12.0 months (95% CI, 7.5-not estimable); the median OS was 22.0 months (95% CI, 15.0-not estimable). The ORR was 61.1% and the DCR was 86.1%. Seventeen of 36 (47.2%) patients experienced treatment-related adverse effects (AEs) of any grade. The most common AE was reactive cutaneous capillary endothelial proliferation (25.0%). Five (13.9%) patients experienced grade ≥3 treatment-related AEs, including decreased lymphocyte (5.6%), bullous dermatitis (2.8%), decreased platelet count (2.8%), and deep-vein thrombosis (2.8%). CONCLUSIONS: External radiotherapy plus camrelizumab, as first-line therapy, met its primary endpoint and showed antitumor activity and low toxicity levels in patients with unresectable iCCA without distant metastases, warranting further investigation. TRIAL REGISTRATION: NCT03898895. Registered 2 April 2019.