Checkpointinhibitoren in der Tumortherapie

In recent years, a breakthrough in tumor therapy was achieved with the development of checkpoint inhibitors. Checkpoint inhibitors activate the immune defense against tumors by overcoming the inhibitory effect of specific cell surface proteins acting as control points, the so-called checkpoints. This article provides an overview of the mode of action of approved checkpoint inhibitors and the status of current clinical development.The previously approved checkpoint inhibitors, monoclonal antibodies directed against the checkpoints CTLA‑4 and PD-1/PD-L1, are used in various tumor entities (including lung, kidney, and urothelial carcinoma; head and neck cancer; melanoma; and Hodgkin lymphoma). For the first time, long-term survival has been achieved in some of these patients with advanced tumors. Unfortunately, this efficacy can be observed only in a small proportion of the treated patients, depending on the tumor indication. Improved efficacy is envisioned by patient selection via predictive biomarkers and the development of combination therapies. Mandatory testing of the expression level of the predictive PD-L1 biomarker is already required in some indications to select patients with an enhanced benefit/risk relationship

The EMA assessment of pembrolizumab as monotherapy for the first-line treatment of adult patients with metastatic microsatellite instability-high or mismatch repair deficient colorectal cancer

On 21 January 2021, the European Commission amended the marketing authorisation granted for pembrolizumab to include the first-line treatment of microsatellite instability-high (MSI-H) or mismatch repair-deficient (dMMR) metastatic colorectal cancer (mCRC) in adults. The recommended dose of pembrolizumab was either 200 mg every 3 weeks or 400 mg every 6 weeks by intravenous infusion. Pembrolizumab was evaluated in a phase III, open-label, multicentre, randomised trial versus standard of care (SOC: FOLFOX6/FOLFIRI alone or in combination with bevacizumab/cetuximab) as first-line treatment of locally confirmed mismatch repair-deficient or microsatellite instability-high stage IV CRC. Subjects randomised to the SOC arm had the option to crossover and receive pembrolizumab once disease progressed. Both progression-free survival (PFS) and overall survival were primary endpoints. Pembrolizumab showed a statistically significant improvement in PFS compared with SOC, with a hazard ratio of 0.60 [95% confidence interval (CI): 0.45-0.80], P = 0.0002. Median PFS was 16.5 (95% CI: 5.4-32.4) versus 8.2 (95% CI: 6.1-10.2) months for the pembrolizumab versus SOC arms, respectively. The most frequent adverse events in patients receiving pembrolizumab were diarrhoea, fatigue, pruritus, nausea, increased aspartate aminotransferase, rash, arthralgia, and hypothyroidism. Having reviewed the data submitted, the European Medicines Agency’s (EMA’s) Committee for Medicinal Products for Human Use (CHMP) considered that the benefit–risk balance was positive. This is the first time the CHMP has issued an opinion for a target population defined by DNA repair deficiency biomarkers. The aim of this manuscript is to summarise the scientific review of the application leading to regulatory approval in the European Union

The European Medicines Agency review of the initial application of atezolizumab and the role of PD-L1 expression as biomarker for checkpoint inhibitors

Immune checkpoint inhibitors have revolutionised cancer therapeutics. Translational research evaluating the role of biomarkers is essential to identify the ideal target population for these drugs. From a regulatory perspective, the identification of biomarkers and diagnostic assays is strongly encouraged by the European Medicines Agency (EMA). The aim of this article is to analyse the role of programmed death-ligand 1 (PD-L1) expression as a predictive biomarker in relation to the data submitted for the initial assessment of atezolizumab, a monoclonal antibody targeting human PD-L1. On 20 July 2017, atezolizumab was granted a marketing authorisation valid throughout the European Union (EU) for adult patients with (i) locally advanced or metastatic non-small-cell lung cancer (NSCLC) after chemotherapy and (ii) locally advanced or metastatic urothelial carcinoma (UC) after chemotherapy or cisplatin-ineligibility. Initially, these indications were not restricted by the level of PD-L1 expression, but preliminary data from an ongoing phase III trial in patients with UC led to a restriction in the UC indication to cisplatin-ineligible patients whose tumours have ≥5% PD-L1 expression. Still, the role of PD-L1 expression as predictive biomarker for atezolizumab therapy remains inconclusive and further research is needed. Data in this paper came from the scientific review leading to the initial regulatory approval of atezolizumab in the EU and its complementary application for indication (EMEA/H/C/004143/II/0010). The full scientific assessment report and product information are available on the EMA website (www.ema.europa.eu)