Envafolimab - first PD-1/PD-L1 antibody to be administered by subcutaneous injection for microsatellite instability-high or deficient mismatch repair advanced solid tumors

Therapeutic antibodies in oncology: an immunopharmacological overview

The biotechnological development of monoclonal antibodies and their immunotherapeutic use in oncology have grown exponentially in the last decade, becoming the first-line therapy for some types of cancer. Their mechanism of action is based on the ability to regulate the immune system or by interacting with targets that are either overexpressed in tumor cells, released into the extracellular milieu or involved in processes that favor tumor growth. In addition, the intrinsic characteristics of each subclass of antibodies provide specific effector functions against the tumor by activating antibody-dependent cellular cytotoxicity, complement-dependent cytotoxicity, and antibody-dependent cellular phagocytosis, among other mechanisms. The rational design and engineering of monoclonal antibodies have improved their pharmacokinetic and pharmacodynamic features, thus optimizing the therapeutic regimens administered to cancer patients and improving their clinical outcomes. The selection of the immunoglobulin G subclass, modifications to its crystallizable region (Fc), and conjugation of radioactive substances or antineoplastic drugs may all improve the antitumor effects of therapeutic antibodies. This review aims to provide insights into the immunological and pharmacological aspects of therapeutic antibodies used in oncology, with a rational approach at molecular modifications that can be introduced into these biological tools, improving their efficacy in the treatment of cancer.

The Trend of the Treatment of Advanced Hepatocellular Carcinoma: Combination of Immunotherapy and Targeted Therapy

OPINION STATEMENT

Hepatocellular carcinoma (HCC) is a common type of tumor worldwide. The development of systemic treatment of advanced HCC has remained stagnant for a considerable period. During the last years, a series of new treatment regimens based on the combination of immunotherapeutic drugs and targeted drugs have been gradually developed, increased the objective response rate (ORR), overall survival (OS), and progression free survival (PFS) of HCC patients. Among the different combination therapy groups, atezolizumab plus bevacizumab and sintilimab plus IBI-305 seem to have unique advantages, while head-to-head comparisons are still needed. A comprehensive understanding of the developments, the ongoing clinical trials and the mechanisms of combination of immunotherapy and targeted therapy might lead to the development of new combination strategies and solving current challenges such as the molecular biomarkers, the clinical administration order of drugs and the second-line treatments after combination therapy.

Model-informed drug development of envafolimab, a subcutaneously injectable PD-L1 antibody, in patients with advanced solid tumors

BACKGROUND AND OBJECTIVES

Envafolimab is the first and only globally approved subcutaneously injectable PD-L1 antibody for the treatment of instability-high (MSI-H) or DNA mismatch repair deficient (dMMR) advanced solid tumors in adults, including those with advanced colorectal cancer that has progressed after treatment with a fluoropyrimidine, oxaliplatin, and irinotecan. The aim of this investigation was to examine the pharmacokinetic and exposure-response (E-R) profile of envafolimab in patients with solid tumors to support the approval of fixed and alternative dose regimens.

METHODS

In this study, a population pharmacokinetic (PopPK) modeling approach will be employed to quantitatively evaluate intrinsic and extrinsic covariates. Additionally, PopPK-estimated exposure parameters were used to evaluate E-R relationship for safety and efficacy to provide a theoretical basis for recommending optimal treatment regimens. Simulations were performed on the dosing regimens of body weight-based regimen of 2.50 mg/kg QW, fixed dose 150 mg QW, and 300 mg Q2W for the selection of alternative dosing regimens. Data from 4 clinical studies (NCT02827968, NCT03101488, NCT03248843, and NCT03667170) were utilized.

RESULTS

The PopPK dataset comprised 182 patients with 1810 evaluable envafolimab concentration records. Finally, a one-compartment model incorporating first-order absorption, first-order linear elimination, and time-dependent elimination according to an Emax function was found to accurately describe the concentration-time data of envafolimab in patients with advanced solid tumors. Creatinine clearance and country were identified as statistically significant factors affecting clearance, but had limited clinical significance. A relative flat exposure-response relationship was observed between early measures of safety and efficacy to verify that no dose adjustment is required. Simulation results indicated that 2.50 mg/kg QW, 150 mg QW, and 300 mg Q2W regimen yield similar steady-state exposure.

CONCLUSIONS

No statistically significant difference was observed between weight-based and fixed dose regimens. Model-based simulation supports the adoption of a 150 mg weekly or 300 mg biweekly dosing regimen of envafolimab in the solid tumor population, as these schedules effectively balance survival benefits and safety risks.

Neoadjuvant envafolimab in a patient with MSI-H/dMMR colon cancer: a case report and literature review

Clinical evidences of neoadjuvant immunotherapy in patients with mismatch repair deficient/microsatellite instability-high status (dMMR/MSI-H) colorectal cancer have not been well received. A 36-year-old man complained of recurrent right upper quadrant pain for more than 1 year, and the symptoms were not significantly relieved after 10 days of oral Changyanning tablet. The patient was finally diagnosed as dMMR/MSI-H colon cancer. Tumor regression was achieved after seven cycles of envafolimab treatment, and the patient obtained postoperative pathological complete response (pCR). Here, we report a case of MSI-H/dMMR transverse colon cancer, who obtained pCR after neoadjuvant envafolimab (a novel subcutaneous single-domain anti-PD-L1 antibody) with a favorable safety profile, aiming to enhance the experiences of comprehensive diagnosis and treatment of colon cancer.

Chidamide plus envafolimab as subsequent treatment in advanced non-small cell lung cancer patients resistant to anti-PD-1 therapy: A multicohort, open-label, phase II trial with biomarker analysis

BACKGROUND

Combination of chidamide and anti-PD-L1 inhibitor produce synergistic anti-tumor effect in advanced NSCLC patients resistant to anti-PD-1 treatment. However, the effect of chidamide plus envafolimab has not been reported.

AIMS

This study aimed to evaluate the efficacy of chidamide plus envafolimab in advanced NSCLC patients resistant toanti-PD-1 treatment.

MATERIALS AND METHODS

Eligible advanced NSCLC patients after resistant to anti-PD-1 therapy received chidamide and envafolimab. The primary endpoint was objective response rate (ORR). The secondary end points included disease control rate (DCR), progression-free survival (PFS), and safety. The expression of histone deacetylase 2 (HDAC2), PD-L1, and blood TMB (bTMB) was also analyzed.

RESULTS

After a median follow-up of 8.1 (range: 7.6-9.2) months, only two patients achieved partial response. The ORR was 6.7% (2/30), DCR was 50% (15/30), and median PFS (mPFS) was 3.5 (95% confidence interval: 1.9-5.5) months. Biomarker analysis revealed that patients with high-level HDAC2 expression had numerically superior ORR (4.3% vs. 0), DCR (52.2% vs. 0) and mPFS (3.7 vs. 1.4m). Patients with negative PD-L1 had numerically superior DCR (52.2% vs. 33.3%) and mPFS (3.7m vs. 1.8m), so were those with low-level bTMB (DCR: 59.1% vs. 16.7%, mPFS: 3.8 vs.1.9m). Overall safety was controllable.

DISCUSSION

High HDAC2patients showed better ORR, DCR, and PFS. In addition, patient with negative PD-L1 and low-level bTMB had better DCR and PFS. This may be related to the epigenetic function of chidamide. However, the sample size was not big enough, so it is necessary to increase sample size to confirm the conclusion.

CONCLUSION

Combination of chidamide and envafolimab showed efficacy signals in certain NSCLC patients. But further identification of beneficial population is necessary for precision treatment.

A multicenter, real-world study on effectiveness and safety of first-line modified PD-1 inhibitors with chemotherapy in advanced non-small cell lung cancer (aNSCLC) with drive gene-negative

OBJECTIVES

The use of immune checkpoint inhibitors, particularly PD-1 inhibitors, has revolutionized the treatment of advanced tumors and shown significant improvements in patient survival rates. However, which PD-1 inhibitor is more effective and safer for a specific indication remains unclear. To address this problem, our study aimed to evaluate the effectiveness and safety of different PD-1 inhibitors in combination with chemotherapy as first-line therapy for individuals with advanced non-small-cell lung cancer (NSCLC) without driver genes in the real world.

MATERIALS AND METHODS

We conducted a retrospective study of individuals diagnosed with aNSCLC who received immune checkpoint inhibitors (ICIs) with modified PD-1 inhibitors, including Sintilimab, Toripalimab, Tislelizumab, Camrelizumab, or Pembrolizumab as first-line treatment between March 5th, 2016 and October 20th, 2022. We assessed demographic and clinical information and analyzed clinical response, survival outcomes, and safety profiles. The primary endpoint was overall survival (OS), and the secondary endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety.

RESULTS

As of the date cut-off on October 20th, 2022, the median follow-up time was 20.62 months. A total of 204 patients were enrolled in the study, including 56 (27.5%) patients receiving modified PD-1 inhibitors (Sintilimab, Toripalimab, Tislelizumab, or Camrelizumab) in combination with chemotherapy and 148 (72.5%) patients receiving Pembrolizumab in combination with chemotherapy. In the overall cohort, the median overall survival (OS) was 26.9 months (95%CI, 22.3-31.6), the median progression-free survival (PFS) was 8.4 months (95%CI, 6.9-9.8), and the objective response rate (ORR) and disease control rate (DCR) were 47.6% (95%CI, 29.9-43.6) and 84.3% (95%CI, 78.4-88.9). The mOS of modified PD-1 inhibitors group and Pembrolizumab group were 30.7 (95%CI, 17.3-44.4) months and 26.8 (95%CI, 22.2-31.4) months. The mPFS of two groups were 8.3(95%CI, 6.9-9.6) months and 8.8 (95%CI, 6.9-10.7) months, respectively. There was no statistical difference between the two groups in terms of OS or PFS. The ORR for the two groups was 48.2% (95%CI, 34.8-61.8) and 47.3% (95%CI, 39.1-5.6), respectively. However, due to the limited sample size, the difference was not statistically significant. On the other hand, the DCR tended to be higher in the Pembrolizumab group (86.5%; 95%CI, 79.7-91.4) compared to the modified PD-1 inhibitors group (78.6%; 95%CI, 65.2-87.9), and this difference was statistically significant (p = 0.006). In terms of safety, both groups exhibited favorable clinical safety profiles. The only two types of potentially immune-related adverse events reported were pneumonitis and reactive cutaneous capillary endothelial proliferation (RCCEP).

CONCLUSIONS

The modified PD-1 inhibitors showed comparable survival outcomes and manageable safety profiles in NSCLC compared to Pembrolizumab. Moreover, these inhibitors exhibited improved accessibility and economic outcomes compared to Pembrolizumab. While there were similarities in drug-related and immunotherapy-related adverse reactions between the modified PD-1 inhibitors and Pembrolizumab, there were some slight differences. Further prospective and retrospective studies would be necessary to validate these findings beyond the scope of the CTONG1901 study.

A retrospective study on the efficacy and safety of Envafolimab, a PD-L1 inhibitor, in the treatment of advanced malignant solid tumors

Envafolimab, a PD-L1 inhibitor, has demonstrated potential in treating advanced malignant solid tumors (AMST). To study its' efficacy and safety in AMST, our retrospective study recruited 64 patients with various AMST, and treated with Envafolimab (400 mg every 3 weeks). We divided the patients into two cohorts: Cohort 1 (25 patients) receiving Envafolimab as first-line therapy, and Cohort 2 (39 patients) receiving it as second-line or subsequent therapy. Our analysis focused on Envafolimab's efficacy and safety. Over a median follow-up of 7.1 months, Cohort I reported a Disease Control Rate (DCR) of 72.0% and an Objective response rate (ORR) of 12.0%, while Cohort II had a DCR of 51.3% and an ORR of 5.1%. Notably, patients with more than four treatment cycles showed higher DCR and longer Progression-Free Survival (PFS) than those with fewer cycles. Adverse events were observed in 68.8% of patients, with severe events (CTCAE grade 3/4) in 14.1%. Most adverse events were mild, leading to treatment discontinuation in only 3.1% of patients, with no life-threatening events reported. In summary, Envafolimab is a safe and effective treatment for AMST, in both initial and later therapy stages, particularly with extended treatment duration, meriting further clinical trials.

Long-term survival in a patient with multiple metastatic gastric cancer treated with PTX plus emvolimab and disitamab vedotin: case report and treatment experience: A case report

RATIONALE

Most Chinese patients with locally advanced gastric cancer at diagnosis have an overall 5-year survival rate of <50%. Surgical resection alone is not suitable for patients with locally advanced gastric cancer. Currently, comprehensive treatment is the focus of locally advanced gastric cancer.

PATIENTS CONCERNS

The patient, a 56-year-old female, was admitted to the hospital because of "4 + months of double hydronephrosis found during a physical examination." Who was admitted for computer tomography and gastroscopy examinations, and take pathological tissue specimens during endoscopic examination.

DIAGNOSES

Computed tomography assessment indicated ulcerative gastric cancer with an abdominal implant, bladder, and bone metastases. An endoscopic examination revealed that the ulcer of the gastric angle was huge, and through relevant auxiliary examinations, the diagnosis of this disease is gastric cancer complicated with multiple metastases to bladder, rectum, lumbar spine, and peritoneum. Clinically diagnosed as cT4bN3M1.

INTERVENTIONS

The patient is currently undergoing first, second, and third line neoadjuvant therapy, combined with immunotherapy, targeted therapy, neoadjuvant intraperitoneal systemic chemotherapy, nutritional support, and other treatment plans.

OUTCOMES

After 15 cycles of treatment, the progression-free survival had reached 15 months. The patient had an NRS2002 score of 1, an ECOG score of I, a quality of life score of 55, albumin of 35.27 g/L, and a decrease in abdominal and pelvic fluid accumulation and exudation compared to before.

LESSONS

We demonstrated high survival of almost 3 years in a patient with gastric cancer that was complicated by bone, peritoneal, rectal, and bladder metastases. The combination of immunotherapy, targeted therapy, and neoadjuvant intraperitoneal systemic chemotherapy, along with the maintenance of nutritional status and CTCs could be a valuable modality for the subsequent treatment and observation of similar patients.

Application of peptide barcoding to obtain high-affinity anti-PD-1 nanobodies

Cancer treatment has been revolutionized by immune checkpoint inhibitors, which regulate immune cell function by blocking the interactions between immune checkpoint molecules and their ligands. The interaction between programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) is a target for immune checkpoint inhibitors. Nanobodies, which are recombinant variable domains of heavy-chain-only antibodies, can replace existing immune checkpoint inhibitors, such as anti-PD-1 or anti-PD-L1 conventional antibodies. However, the screening process for high-affinity nanobodies is laborious and time-consuming. Here, we identified high-affinity anti-PD-1 nanobodies using peptide barcoding, which enabled reliable and efficient screening by distinguishing each nanobody with a peptide barcode that was genetically appended to each nanobody. We prepared a peptide-barcoded nanobody (PBNb) library with thousands of variants. Three high-affinity PBNbs were identified from the PBNb library by quantifying the peptide barcodes derived from high-affinity PBNbs. Furthermore, these three PBNbs neutralized the interaction between PD-1 and PD-L1. Our results demonstrate the utility of peptide barcoding and the resulting nanobodies can be used as experimental tools and antitumor agents.

Identification of ZBTB4 as an immunological biomarker that can inhibit the proliferation and invasion of pancreatic cancer

BACKGROUND

Zinc finger and BTB domain-containing protein 4 (ZBTB4) belongs to the zinc finger protein family, which has a role in regulating epigenetic inheritance and is associated with cell differentiation and proliferation. Previous studies have identified aberrant ZBTB4 expression in cancer and its ability to modulate disease progression, but studies on the immune microenvironment, immunotherapy and its role in cancer are still lacking.

METHODS

Human pan-cancer and normal tissue transcriptome data were obtained from The Cancer Genome Atlas. The pan-cancer genomic alteration landscape of ZBTB4 was investigated with the online tool. The Kaplan-Meier method was used to evaluate the prognostic significance of ZBTB4 in pancreatic cancer. In parallel, ZBTB4 interacting molecules and potential functions were analyzed by co-expression and the correlation between ZBTB4 and immune cell infiltration, immune modulatory cells and efficacy of immune checkpoint therapy was explored. Next, we retrieved the Gene Expression Omnibus database expression datasets of ZBTB4 and investigated ZBTB4 expression and clinical significance in pancreatic cancer by immunohistochemical staining experiments. Finally, cell experiments were performed to investigate changes in pancreatic cancer cell proliferation, migration and invasion following overexpression and knockdown of ZBTB4.

FINDINGS

ZBTB4 showed loss of expression in the majority of tumors and possessed the ability to predict cancer prognosis. ZBTB4 was closely related to the tumor immune microenvironment, immune cell infiltration and immunotherapy efficacy. ZBTB4 had good diagnostic performance for pancreatic cancer in the clinic, and ZBTB4 protein expression was lost in pancreatic cancer tumor tissues. Cell experiments revealed that overexpression of ZBTB4 inhibited the proliferation, migration and invasion of pancreatic cancer cells, while silencing ZBTB4 showed the opposite effect.

CONCLUSIONS

According to our results, ZBTB4 is present in pancreatic cancer with aberrant expression and is associated with an altered immune microenvironment. We show that ZBTB4 is a promising marker for cancer immunotherapy and cancer prognosis and has the potential to influence pancreatic cancer progression.