During 2017, two new programmed death-ligand 1 (PD-L1) inhibitors, Pfizer and Merck’s Bavencio (avelumab) and AstraZeneca’s Imfinzi (durvalumab), were added to the growing list of marketed checkpoint inhibitors (CPIs), while Bristol Myer Squibb’s (BMS) Opdivo (nivolumab), Merck & Co.’s Keytruda (pembrolizumab), and Roche’s Tecentriq (atezolizumab) expanded their labels.
Bavencio is the first CPI immunotherapy approved for metastatic Merkel Cell Carcinoma (MCC), a rare skin cancer affecting 1,500 people in the US each year. In addition, both Bavencio and Imfinzi received FDA approvals for the treatment of advanced urothelial carcinoma (UC) in 2017. GlobalData forecasts modest uptake for Bavencio and Imfinzi due to the low incidence of MCC and strong competition in the UC space where Tecentriq, Opdivo, and Keytruda are also marketed.
GlobalData also anticipates that the growth of the market share for the two anti-PD-L1 therapies will be accelerated by approvals in other oncology indications, specifically metastatic renal cell carcinoma (mRCC) and non-small cell lung cancer (NSCLC). CPIs are not yet approved for the treatment of first-line (1L) mRCC, and Bavencio is favourably positioned in this disease in combination with Pfizer’s tyrosine kinase inhibitor (TKI), Inlyta (axitinib).
Although the frontrunners in 1L mRCC are BMS’s CPI combination of Opdivo + Yervoy (anti-CTLA4) and Roche’s Tecentriq + Avastin (bevacizumab), the preliminary findings at the 2018 American Society of Clinical Oncology (ASCO) Genitourinary Cancer Symposium suggest that a CPI paired with a more selective TKI, such as Inlyta, is a highly active regimen with a safety profile superior to that of an anti-PD-1 + anti-CTLA4 combination.
Checkpoint immunotherapy approvals in 2017
Source: GlobalData. ADC = adenocarcinoma; CRC = colorectal cancer; dMMR = mismatch repair deficient; GC = gastric cancer; GEJ = gastroesophageal junction; HCC = hepatocellular carcinoma; JP = Japan; MCC = Merkel Cell Carcinoma; MSI-H = microsatellite instability high; nonsq = nonsquamous; NSCLC = non-small cell lung carcinoma; PD-L1 = programmed death-ligand 1; R/R cHL = relapsed/refractory classic Hodgkin lymphoma; UC = urothelial carcinoma; SCCHN = squamous carcinoma of the head and neck
Meanwhile, Imfinzi is strategically positioned for the maintenance treatment of locally advanced NSCLC that has responded to initial treatment with chemoradiotherapy. Imfinzi could be the first CPI approved for this setting, as the other CPIs have mainly been positioned for the treatment of patients with metastatic NSCLC.
If Imfinzi strengthens the existing strong progression-free survival (PFS) data with a significant survival benefit, it will likely gain first-to-market advantage and offer extended treatment duration in the maintenance setting, dramatically expanding its market share in the oncology space. Moreover, an increased uptake of Imfinzi in early-stage disease will threaten the share of other CPIs used in metastatic NSCLC by downsizing their respective target patient pool due to prior anti-PD-L1 exposure.
Following its 2016 launches in second-line (2L) UC and NSCLC, Tecentriq is on track to be the second CPI indicated for the treatment of 1L NSCLC, after Keytruda. Tecentriq’s combination regimen with Avastin and chemotherapy met the PFS co-primary endpoint in the IMpower150 trial. With the overall survival readout expected in H1 2018, Roche’s three-drug regimen will have its debut in 1L nonsquamous NSCLC in late 2018 to early 2019.
The failure of Opdivo monotherapy in 2016, BMS’s decision not to pursue accelerated approval for Opdivo + Yervoy in early 2017, and a lack of PFS benefit shown with Imfinzi + tremelimumab (anti-CTLA4) provides Merck & Co. with more time to establish Keytruda in 1L NSCLC. The approval of Keytruda + chemotherapy in 1L nonsquamous NSCLC regardless of PD-L1 expression further cements Keytruda’s leap in the lucrative NSCLC space.
In 2017, the medical community witnessed the first tumour-agnostic approval of an oncology drug, signalling a paradigm shift in cancer treatment. Keytruda’s approval for microsatellite instability high (MSI-H) or mismatch repair deficient (dMMR) solid tumours makes the CPI the first cancer therapy approved for use based on a biomarker regardless of tumour type. Unlike PD-L1 testing, a lack of variability in detecting MSI or deficiency in MMR will result in routine testing for this biomarker in medical practice and lead to the rapid adoption of Keytruda across a range of tumour types.
GlobalData (2017). Non-Small Cell Lung Cancer (NSCLC) – Dynamic Market Forecast to 2025, August 2017, GDHC001FS
GlobalData (2017). PharmaFocus: Visual Analysis of Immuno-Oncology Development and Opportunities, August 2017, GDHC009PFR