Kazia Therapeutics Phase II Paxalisib glioblastoma study shows positive overall survival signal data

Kazia Therapeutics Ltd (ASX:KZA) has released positive interim data from its ongoing phase II study of paxalisib (formerly GDC-0084) in glioblastoma, the most common and most aggressive form of primary brain cancer.

Thirty patients were enrolled to this study, comprising 9 in Part A and 21 in Part B.

Interim analysis of Part A showed median overall survival of 17.7 months, representing a clinically meaningful extension of life when compared to the 12.7 months associated with the existing standard of care, temozolomide.

In addition, the interim analysis of all evaluable patients (Parts A and B) shows median progression-free survival of 8.5 months, broadly in line with previous analysis and comparing favourably to the 5.3 months associated with temozolomide.

The longest-treated patient remains progression-free 19 months after diagnosis.

“Excellent result”

Kazia chief executive officer Dr James Garner said: “This is an excellent result and we are delighted with the emerging data.

“The ‘gold standard’ for any new cancer treatment is the ability to extend life – an especially challenging goal in a disease such as glioblastoma – and this data provides our first evidence that paxalisib may achieve this objective in a very challenging patient population.”

Kazia acknowledges that the comparison between different studies is always imprecise, but the magnitude of the numerical difference provides powerful evidence that treatment with paxalisib may extend life in this patient group.

Commercial opportunity

Before losing patent protection, temozolomide achieved peak sales in excess of US$1 billion per annum, which provides an indication of the commercial opportunity associated with a new treatment for glioblastoma.

Garner said: “There have not been any new drug treatments for newly-diagnosed glioblastoma patients for over 20 years and we aspire to change that situation.

“We believe that paxalisib is rapidly becoming one of the most promising drug candidates in the global pipeline for this very challenging disease and we will be working strenuously to make it available to patients as quickly and efficiently as possible.

“The study continues to follow a number of patients who remain on treatment, and we currently expect to report a further data read-out in the second half of the year.”

Next steps

Approximately half the enrolled patients remain on drug and both overall survival and progression-free survival figures may further improve as the trial progresses towards conclusion.

The phase II study remains ongoing, with approximately half of the total enrolled patient population still receiving drug at the time of analysis and several additional patients still in follow-up.

At this stage, Kazia expects to present further data in the second half of 2020, and final data in the first half of 2021.

Four other studies are also underway with paxalisib in different forms of brain cancer, with initial efficacy data anticipated during 2020.

In parallel to completion of this phase II study Kazia has begun preparatory activities to bring paxalisib into the international platform study, GBM AGILE, which is intended to provide data to support FDA approval for paxalisib in glioblastoma.

Kazia continues to expect first patient into the paxalisib arm in the second half of 2020.

Trading halt

Kazia is in a trading halt pending the release of an announcement regarding a capital raising.

Unless ASX decides otherwise, the securities will remain halted until the earlier of the start of normal trading on Wednesday, April 15, 2020, or when the announcement is released to the market.

Shares in the company, which has a market cap of approximately $32.1 million, last traded at 44.5 cents.

Story by ProactiveInvestors