Tarceva - Erlotinib geeft hoog significant langere ziektevrije tijd en overleving als eerste lijnsbehandeling voor niet-klein-cellige longkanker met juiste EGRF receptor expressie.

11 oktober 2010: Bron: Medscape en 35th European Society for Medical Oncology Congress: Abstract LBA14. Presented October 9, 2010.

Tarceva - Erlotinib geeft als eerste lijnsbehandeling tegenover chemo (gemcitabine en carboplatin) een verdriedubbeling van de ziektevrij tijd voor longkankerpatienten (niet-klein-cellig) met receptoren met de juiste EGRF expressie (83% vs 36%, respectively; P = .0000). Dit blijkt uit een gerandomiseerde studie bij Chinese longkankerpatienten. opvallend dat in artikel over deze studie wordt opgemerkt dat in China 30% van de longkankerpatienten de jusite EGRF receptorenexpressie zouden hebben tegenover slechts 10% in Europa en Amerika. Zou dit betekenen dat er in Europa en Amerika nog weinig aandacht is voor die meting en selectie? Zie ook artikel in linkerkolom hoe in Japan gemakkelijk de expressie van longtumoren kan worden vastgesteld. Hier een citaat met de resultaten uit een groot artikel uit Medscape over deze studie:

Progression-Free Survival Significantly Longer

The study was carried out in a Chinese population who had not received previous chemotherapy and had an Eastern Cooperative Oncology Group performance status of 0 to 2 and measurable disease. Patients were randomly assigned to receive either erlotinib at 150 mg/day until unacceptable toxicity or progressive disease (n = 82) or combination chemotherapy (n = 72) of gemcitabine and carboplatin (gemcitabine, 1000 mg/m², on days 1 and 8, plus carboplatin [area under the curve, 5] on day 1, every 3 weeks for up to 4 cycles).

Approximately one third (34%) of patients with advanced NSCLC had an EGFR receptor mutation, and 52% of these patients had exon 19 deletion type of EGFR-activating mutation in contrast to exon 21 L858R mutation.

Data analysis showed progression-free survival, the primary endpoint, was significantly longer in patients receiving erlotinib vs those receiving the gemcitabine–carboplatin combination (13.1 vs 4.6 months, respectively; hazard ratio, 0.16; 95% confidence interval, 0.10 - 0.26; P < .0001).

Progression was defined as disease worsening by 20% or more in lesions or development of new lesions. The objective response rate was significantly improved in patients receiving erlotinib vs gemcitabine–carboplatin (83% vs 36%, respectively; P = .0000). In addition, the disease control rate was also more favorable with erlotinib (disease control rate — complete response + partial response + stable disease — was 96% vs 82%; P = .002).

Dr. Zhou reported a lower incidence of adverse events and serious adverse events with erlotinib vs the gemcitabine–carboplatin combination. No unexpected adverse events or interstitial lung disease-like events were reported in either group.

Dr. Zhou explained that the overall EGFR mutation rate in the white population with NSCLC is about 10%, but in the Chinese population, that figure increases to 30%. Of the 549 patients screened for this study, the mutation rate was 34%.

A similar study in the white population, known as the EURTAC study, is currently ongoing.

In conclusion, Dr. Zhou suggested that erlotinib should be the treatment of choice in these patients. "The impact of using erlotinib is great when moved to front-line treatment in patients with EGFR mutation," he said. "This is a big step forward, and the hazard ratio of 0.16 could be the new benchmark for studies.

"I think erlotinib should be preferred over conventional chemotherapy in these particular populations," he added.

ziektevrije tijd, eerste lijns behandeling, overleving, EGRF receptor, Iressa, Tarceva