AbbVie trial backs chemo-free Imbruvica combo regimen

The pairing of of AbbVie’s Imbruvica and Roche’s Gazyva has hit the mark in a chronic lymphocytic leukaemia trial – raising the prospect of a new chemotherapy-free combination regimen for previously untreated CLL patients.

The iLLUMINATE trial showed that oral BTK inhibitor Imbruvica (ibrutinib) plus anti-CD20 injection Gazyva (obinutuzumab) was more effective than Gazyva plus chemo (chlorambucil) in treatment-naïve, older patents (aged 65 or more) with either CLL or small lymphocytic leukaemia (SLL) – a different form of the same disease.

The top-line data isn’t being made available just yet, but in a statement AbbVie said the duo extended progression-free survival (PFS) compared to the active control arm, adding that it will be sharing the data with regulators, in the hope of bringing “the first chemotherapy-free CD20 combination in first-line CLL treatment” to market.

The trial ties in with AbbVie’s strategy of expanding use of Imbruvica as a first-line CLL treatment and, while Gazyva has been something of a slow burner for Roche since its launch in that setting in 2014, it has started to gain momentum with sales rising 41% to CHF 278m last year.

The combination of Gazyva and chlorambucil is now recommended as a first-line therapy for CLL by the US National Comprehensive Cancer Network, which deems it a category 1 treatment, ie one with a high level of evidence backing its use, so outperforming it is a big win for the combination.

“This chemotherapy-free combination represents a potential new treatment option for patients with CLL," said John Gribben of Barts Cancer Institute in the UK, the lead investigator for the iLLUMINATE study.

“It’s exciting to see the blood cancer treatment paradigm continue to evolve – each advance moves us one step closer to a better standard of care for these patients,” he added.

Imbruvica is already approved for all lines of therapy in CLL, and beating out chlorambucil is not a big surprise as AbbVie’s drug comprehensively outperformed the chemotherapy as a monotherapy in the head-to-head RESONATE-2 trial.

The trial was the basis of Imbruvica’s approval in 2016 as a chemo alternative in treatment-naïve CLL, and the disease accounts for the lion’s share of the drug’s sales, which grew almost 39% to $762m in the first quarter of this year, topping estimates. AbbVie is predicting sales of $3.3bn this year, well on course for its peak sales target of $6bn-$7bn.

AbbVie’s head of R&D Michael Severino said on the company’s first-quarter results call that the strategy is to build a “body of evidence” for Imbruvica – both as a monotherapy and in combination – across different CLL segments “including young and fit patients and the watch-and-wait population”.