“Data from a phase 3 trial demonstrate combination dabrafenib and trametinib was superior to dabrafenib plus placebo for improved PFS in patients with BRAFV600-positive metastatic melanoma, according to data presented here at the ASCO Annual Meeting.
“ ‘This is the first melanoma trial, phase 3, to have an active control arm,’ researcher Georgina V. Long, BSc, PhD, MBBS, FRCP, oncologist at Melanoma Institute Australia at the University of Sydney, said of the COMBI-D trial.”
Editor’s note: This story describes the results of a clinical trial, in which volunteer patients are help test a new treatment. The treatment consists of a combination of the targeted therapy drugs dabrafenib and trametinib. Patients treated with the combination lived longer without progression of their cancer than patients who received dabrafenib plus a non-active placebo. Importantly, these results are specific to patients whose tumors have “BRAF V600E” mutations, which doctors can detect via molecular testing.
“There are thousands of drugs that silence many thousands of cancer-causing genetic abnormalities. Some of these drugs are in use now, but many of these drugs are sitting on shelves or could be used beyond the disease for which they were originally approved. Repurposing these drugs depends on matching drugs to targets. A study recently published describes a new database and pattern-matching algorithm that allows researchers to evaluate rational drugs and drug combinations, and also recommends a new drug combination to treat drug-resistant non-small cell lung cancer.”
The US Food and Drug Administration just granted accelerated approval for a treatment that combines two drugs that target melanomas with BRAF mutations — but this was contingent on the results of an ongoing phase III clinical trial. The drugs are the BRAF inhibitor dabrafenib (Tafinlar) and the MEK inhibitor trametinib (Mekinist). Now the latest results of the trial are in and they look good. This combination treatment is not approved elsewhere in the world, and the trial included 423 people from Australia, Europe, and North and South America. Final results are expected later this year and will be presented at a scientific meeting. In addition, another trial is comparing this combination treatment to the BRAF inhibitor vemurafenib (Zelboraf), which is also FDA-approved.
Good news for people with melanomas that have BRAF mutations — the US Food and Drug administration just greenlighted using two targeted treatments at the same time. The two targeted treatments are the BRAF inhibitor Tafinlar (dabrafenib) and the MEK inhibitor Mekinist (trametinib), and both were previously FDA-approved for separate use. Melanomas often become resistant to BRAF inhibitors, and adding the MEK inhibitor could prevent or stave off this resistance.
Two pharmaceutical giants are teaming up on a phase I/II clinical trial to see if their anti-melanoma drugs work better together than on their own. The drugs are GlaxoSmithKline’s Mekinist (trametinib), a U.S. Food and Drug Administration (FDA)-approved MEK inhibitor (a drug that targets MEK proteins), and Pfizer’s palbociclib, an experimental inhibitor of proteins called cyclin dependent kinases. These proteins make cells divide and are abnormally active in many cancers; the FDA has fast-tracked the review of using palbociclib to treat breast cancer. In addition, GlaxoSmithKline is already testing the combination of Mekinist with dabrafenib, the company’s experimental BRAF inhibitor.
We already knew that melanomas can resist BRAF inhibitor drugs by activating a particular cancer pathway (a group of proteins in a cell that work together to control cell multiplication, which can lead to tumor growth)—but new research shows that this resistance can also be caused by activating a second cancer pathway. The first pathway is called MAPK and the second is called PI3K-PTEN-AKT. The researchers studied 100 melanomas that resisted the BRAF inhibitors vemurafenib or dabrafenib, and found that 70% had mutations in the first pathway, while 22% had mutations in the second pathway. Moreover, mutations in both pathways could occur in the same tumor, suggesting that thwarting resistance to BRAF inhibitors may require targeting both pathways with a combination treatment.
Two targeted treatments that are U.S. Food and Drug Administration (FDA)-approved for melanoma may be even more effective together. The drugs are dabrafenib, a BRAF inhibitor, and trametinib, a MEK inhibitor. In a phase II clinical trial with 160 people, the median survival was nearly 2 years with the combination treatment compared to 20 months with dabrafenib alone. These findings were presented at the 10th International Congress of the Society for Melanoma Research in Philadelphia, Pennsylvania. Now, the dabrafenib/trametinib combo has advanced to phase III trials.
Combining cetuximab (Erbitux), bevacizumab (Avastin), and traditional chemotherapy in patients with non-small cell lung cancer (NSCLC) appeared to be safe and effective in a phase II clinical trial. Patients with advanced non-squamous NSCLC received Erbitux and Avastin in addition to carboplatin (Paraplatin) and paclitaxel (Taxol/Abraxane) as first-line treatment, followed by maintenance treatment with Erbitux and Avastin. Tumors shrank in 56% of patients and stopped growing in an additional 21%. Serious side effects were relatively rare; the rate was comparable to that of either Erbitux or Avastin alone. Both Erbitux and Avastin have shown efficacy in NSCLC by themselves, but may be more effective when given together. An ongoing phase III clinical trial will further investigate this drug combination.
In the last few years, patients with the grim diagnosis of metastatic melanoma have gained reasons to feel more hopeful about their chances of beating the disease. Melanoma has become a poster child for new cancer treatment options, with several targeted and immune therapies approved by the U.S. Food and Drug Administration (FDA) and many more in clinical development. Continue reading…