Oncology specialist company Prescient Therapeutics (ASX: PTX) has announced positive interim data from a phase 1b safety study of its lead drug PTX-200 in women with recurrent or persistent platinum-resistant ovarian cancer.
Conducted at the H Lee Moffitt Cancer Centre in the US, the study aims to find a maximum tolerated dose of PTX-200 in combination with standard-of-care chemotherapy drug carboplatin, using a group of 15 female patients treated with up to 25mg/m2 of the drug.
Analysis of the interim data revealed 12 patients (or 80%) displayed disease control after treatment, with 11 women exhibiting a stabilised condition and one having a partial response.
Seven serious adverse events were reported, but only one of those – a case of grade 2 vomiting, which resulted in hospitalisation – was considered “possibly related to PTX-200”.
The drug’s safety profile has been considered acceptable to date, with observed toxicities consistent with what has been seen in using carboplatin alone.
Escalation to the optimal dose of PTX-200 has not yet been completed.
Ovarian cancer remains one of the most common cancers in women.
Australian Government studies estimate it will remain the 10th most commonly-diagnosed cancer among Australian females in 2019, with an estimated 1,510 new cases diagnosed nation-wide.
After frontline treatment with carboplatin, a significant majority of ovarian cancer patients relapse and are eventually deemed platinum-resistant.
Pre-clinical studies involving PTX-200 have already proven the drug can overcome this resistance and synergise with platinum-based chemotherapies.
Prescient chief executive officer Steven Yatomi-Clarke said there are currently very few clinical options for patients who become resistant to carboplatin.
“At this stage of disease, there are few options for these patients … [there is] a severe gap in the market for new drugs for these sort of cancers,” he said.
“Overcoming platinum resistance would be a huge development in the field of ovarian cancer, and PTX-200 is showing early promise as a candidate for achieving this objective.”
It is known that abnormally-high levels of protein kinase B (or Akt) can contribute to a cancer patient’s platinum resistance.
“Our study is attempting to inhibit Akt, and thereby re-sensitise these patients to platinum therapies, effectively reversing and overcoming resistance of the tumour to chemotherapy,” Mr Yatomi-Clarke said.
“To see disease control at an early stage of the study is encouraging, especially given that we are yet to we reach what we believe to be an optimal dose of PTX-200.”
Prescient will seek to continue studying PTX-200 in ovarian cancer within Australia or as an investigator-sponsored study backed by non-dilutive funding.
At midday, shares in Prescient were up 4.60% to $0.091.