Antibody-Drug Conjugates in Solid Tumor Oncology: An Effectiveness Payday with a Targeted Payload

Antibody-drug conjugates (ADCs) are at the forefront of the drug development revolution occurring in oncology. Formed from three main components-an antibody, a linker molecule, and a cytotoxic agent ("payload"), ADCs have the unique ability to deliver cytotoxic agents to cells expressing a specific antigen, a great leap forward from traditional chemotherapeutic approaches that cause widespread effects without specificity. A variety of payloads can be used, including most frequently microtubular inhibitors (auristatins and maytansinoids), as well as topoisomerase inhibitors and alkylating agents. Finally, linkers play a critical role in the ADCs' effect, as cleavable moieties that serve as linkers impact site-specific activation as well as bystander killing effects, an upshot that is especially important in solid tumors that often express a variety of antigens. While ADCs were initially used in hematologic malignancies, their utility has been demonstrated in multiple solid tumor malignancies, including breast, gastrointestinal, lung, cervical, ovarian, and urothelial cancers. Currently, six ADCs are FDA-approved for the treatment of solid tumors: ado-trastuzumab emtansine and trastuzumab deruxtecan, both anti-HER2; enfortumab-vedotin, targeting nectin-4; sacituzuzmab govitecan, targeting Trop2; tisotumab vedotin, targeting tissue factor; and mirvetuximab soravtansine, targeting folate receptor-alpha. Although they demonstrate utility and tolerable safety profiles, ADCs may become ineffective as tumor cells undergo evolution to avoid expressing the specific antigen being targeted. Furthermore, the current cost of ADCs can be limiting their reach. Here, we review the structure and functions of ADCs, as well as ongoing clinical investigations into novel ADCs and their potential as treatments of solid malignancies.

AB0672 Functional capacity and quality of life in patients with systemic sclerosis – data from Moscow register of patients with systemic sclerosis

Background

Systemic sclerosis (SSc) is a multisystem, connective tissue disease characterized by fibrosis of the skin and internal organ involvement, which can influence quality of life and functional capacity. SSc patients show some problems associated with reduced quality of life.

Objectives

Systemic sclerosis (SSc) is a multisystem, connective tissue disease characterized by fibrosis of the skin and internal organ involvement, which can influence quality of life and functional capacity. SSc patients show some problems associated with reduced quality of life.

Methods

In total, 51 patients with SSc were included: 50 women and 1 man (mean age: 63,2 ± 10,1 year, limited SSc 28/diffuse SSc 23, median duration since first non-Raynaud symptom: 10,1 years) who fulfilled the ACR/EULAR classification criteria (2013), filled in questionnaires assessing disability (HAQ, Health Assessment Questionnaire) and quality of life (SF-36, Medical outcomes study Short Form 36 - Physical Component Summary and Mental Component Summary).

Results

Average HAQ in patients with limited and diffuse SSc was 0,66±0,58 and 0,9±0,59. Data analysis showed that 59% of the patients were in the mild to moderate HAQ disability category (0 ⩽ HAQ < 1), 39% in the moderate to severe disability category (1 ⩽ HAQ < 2), and 2% in the severe to very severe disability category (2 ⩽ HAQ ⩾ 3). The SF36 mean scores of the total group were 34,8±8,7 on the Mental Component Summary and 37,0±13,1 on the Physical Component Summary.

Conclusion

Ssc and its complications decrease quality of life and functional capacity. Although validated in SSc, the HAQ disability index underestimates respiratory failure due to interstitial lung disease, gastrointestinal symptoms, cardiovascular complications and severity of Raynaud phenomenon. Alternative measures of functional impairment should be examined. Health-related quality of life, which was assessed by the SF-36 is reduced in both physical and mental domains. It should be taken into account by clinicians for further improvement of treatment and development rehabilitation program.

References

[1]Almeida C, Almeida I, Vasconcelos C. Quality of life in systemic sclerosis. Autoimmun Rev. 2015;14(12):1087-1096

Disclosure of Interests

None declared

AB0674 Providing patients with systemic sclerosis by medical care in Russia: the first data from Moscow Register of Systemic Sclerosis

Background

Systemic sclerosis (SSc) is a multisystem, connective tissue disease characterized by fibrosis of the skin and internal organ involvement, which can influence quality-of-life and functional capacity. 1 The mortality rate is increasing in the United States and Europe; as many as 3.08 persons are affected per 1 million. Changes in lungs and heart, pulmonary hypertension are the most significant reasons of death in patients with systemic sclerosis.2

Objectives

To estimate quality and completeness of medical care in patients with systemic sclerosis in Russia.

Methods

66 patients included in the study. 61 female and 5 male (mean age: 62,48 ± 10,1), among which there were 24 limited SSc (lSSc) and 42 diffuse SSc (dSSc). All patients fulfilled the ACR/EULAR classification criteria. We estimated percentage of patients, who were examined by basic studies: capillaroscopy, functional lung tests, echocardiography, HRCT, fully immunologic study and right heart catheterization etc. and try to understand reasons of incompleteness of these assessments.

Results

Despite the presence of Raynaud’s phenomenon in 85% of patients, capillaroscopy was performed only in 65.21% of them, examination of the esophagus was performed in only 22.92% of patients, with development of dysphagia in 50% of patients. HRCT was performed in 54.71% (25.76% NSIP, 9.09% UIP), right heart catheterization in 4.17% (signs of pulmonary hypertension according to ECHO detected in 42.86% of patients). FLT were performed in mostly patients (86.34%), but it wasn`t fully: measuring of DLCO was realized only in patients with severe desease (22.92% оf patients). That explains its low mean level (61.37% from normal) as opposed to mean FEV1 (90.7% from normal) and FVC (89.47% from normal) level. Fully immunologic study was performed in 35.42% of patients, despite the fact that different autoantibodies showed up in 72.92% of patients (the most common were: antiScl70 41,67%, ACA 22,92%, ANF 52,08%).

Conclusion

According to the results of the study, we have identified a significant decrease in the quality of medical care despite the clinical recommendations and generally accepted standards. We suppose. that the main reasons for this situation are the complex healthcare problems: insufficient competence of doctors, lack of collaboration between related specialties, unavailability of a number of studies within the framework of free medicine and high cost of these studies for the patients themselves, and the lack of time for communication between the doctor and the patient to explain the seriousness of the disease and the nescessity of all parts of examination and treatment.

References

[1]Almeida C, Almeida I, Vasconcelos C. Quality of life in systemic sclerosis. Autoimmun Rev. 2015;14(12):1087-1096

[2]Ungprasert P, Srivali N, Kittanamongkolchai W. Systemic sclerosis and risk of venous thromboembolism: A systematic review and meta-analysis. Mod Rheumatol. 2015 Apr 7. 1-17.

Disclosure of Interests

None declared

Pathological Features of Tumors of the Nervous System in Hereditary Cancer Predisposition Syndromes: A Review

Hereditary cancer predisposition syndromes (HCS) become more recognizable as the knowledge about them expands, and genetic testing becomes more affordable. In this review, we discussed the known HCS that predispose to central and peripheral nervous system tumors. Different genetic phenomena were highlighted, and the important cellular biological alterations were summarized. Genetic mosaicism and germline mutations are features of HCS, and recently, they were described in normal population and as modifiers for the genetic landscape of sporadic tumors. Description of the tumors arising in these conditions was augmented by representative cases explaining the main pathological findings. Clinical spectrum of the syndromes and diagnostic criteria were tabled to outline their role in defining these disorders. Interestingly, precision medicine has found its way to help these groups of patients by offering targeted preventive measures. Understanding the signaling pathway alteration of mammalian target of rapamycin (mTOR) in tuberous sclerosis helped introducing mTOR inhibitors as a prophylactic treatment in these patients. More research to define the germline genetic alterations and resulting cellular signaling perturbations is needed for effective risk-reducing interventions beyond prophylactic surgeries.

Learning Curve and Early Results of Interlaminar and Transforaminal Full-Endoscopic Resection of Lumbar Disc Herniations

Background

Full-endoscopic spinal surgery is an evolving technique. A laborious learning phase is inevitable due to the complexity of the orientation and instrumentation. The goal of the present study is to evaluate a single surgeon’s learning curve and early outcomes in full-endoscopic resection of lumbar disc herniations.

Methods

This was a prospective non-controlled single-surgeon cohort study. In 54 patients with 57 herniations, 41 interlaminar and 16 transforaminal resections were performed. Surgery time, severity of adhesive process in the spinal canal, complication rates and clinical outcomes (VAS, ODI, custom questionnaire, recurrence and re-operation rate) were assessed.

Results

In the interlaminar group, operative time has decreased from 60 ± 20 min in the first 20 operations to 45 ± 14 min in the following 17 (p=0.023). In the transforaminal group, operative time has decreased from 60 ± 16 min in the first 7 operations to 41 ± 12 min in following 9 (p=0.023). Severe adhesive process in spinal canal was associated with duration of symptoms greater than 2 years, longer surgery and higher risk of surgical complications. Four recurrent disc herniations were re-operated using full-endoscopic technique. VAS, ODI and pain medications significantly decreased in both groups and in re-operated patients.

Conclusion

The plateau of the learning curve and good short-term clinical results of full-endoscopic interlaminar and transforaminal surgery may be achieved after twenty operations, given extensive previous experience in microsurgery. Risk of complications at the learning phase may be decreased by excluding the patients with symptoms lasting over two years.