The Abstract for Starpharma’s ESMO poster presentation is up on their website. I have copied and pasted the abstract below.
The Poster presentation is on Sunday 11th September.
The abstract was submitted to ESMO before the deadline of early May this year. (The abstract effectively acts as an application to present at ESMO). I have compared all the statistics in this abstract to the announcement back in November 2021 regarding interim results. They are identical, so there is nothing new in this abstract.
The upcoming Poster will have a much more detailed presentation of information than the abstract and IMHO, should (I strongly suspect will, but cannot guarantee) present the FINAL RESULTS for the Prostate Cancer cohort of the DEP Cabazitaxel phase 2 trial. (At the time of releasing the interim results - Nov 21 - there were 5 final prostate cancer patients yet to complete their treatment. Their final results are very likely to be available now). Final results would contain additional vital key data such as time-to-progression (progression-free survival).
We all know the results will be good, judging from the interim results, especially for such heavily pre-treated and older patients.
According to the ESMO website, presentations are subject to an embargo:
‘Data and information beyond what is included in all accepted abstracts, for example full data sets, may only be made public at the start of the official programme session during which the study is presented.’
So, from the above, we can see that the final results (if available, which is very likely) from the prostate cancer cohort of the trial have been under embargo – ending this Sunday 11/9/2022.
From all of this, I think there is a very good chance we could have an announcement to the market regarding the full results (full data read-out) of the prostate cancer cohort before the opening of the market this Monday morning (to satisfy both embargo requirements and market disclosure requirements).
Prostate cancer is the ‘CORE’ INDICATION being explored in the DEP Cabazitaxel phase 2 trial. As standard Cabazitaxel is already used in mCRPC this cohort can be compared to historical trials of similar groups of patients using standard cabazitaxel to draw conclusions about any likely improvements in safety or efficacy afforded by using the DEP dendrimer platform technology (also taking into account their more heavily pre-treated status and older average age compared with past standard cabazitaxel trials in prostate cancer).
The phase 2 trial has continued to recruit patients for promising ‘EXPLORATORY’ INDICATIONS (cancers against which the original drug has no demonstrated useful clinical effect – gastro-oesophageal and ovarian cancers) assessing for efficacy signals that indicate possible wider applications for the new DEP version compared with the original drug.
People on this forum have been dismayed that recruitment in all three internal phase 2 trials continues for ‘exploratory’ indications and for combination therapies but, as I have said before, it does not concern me that this is happening. Why not explore these drugs further while negotiating licencing deals? (or even beyond a licencing deal, if it suits the licencee, while setting up phase 3 trials in core indications?) It can only add further value over time.
As I have stated before, I believe it is the enhanced safety and efficacy results of the CORE INDICATION cohorts in each of our phase 2 DEP trials that will be the key information (proof-of-concept for the DEP platform) assessed by BIG PHARMA considering licencing of these drugs. Strong efficacy signals in exploratory indications and combination studies are an extra bonus, suggesting wider future possible indications for the DEP version of the drug. I believe that there is no requirement for any of these open-label trials to be completely ‘finished’, beyond readout of the CORE INDICATIONS, for a big pharma to make the decision to sign a licence deal. Big pharma will make a decision when satisfied that what they are getting is good value. This could be at any time. Starpharma has been saying for a long time now that they are engaged in discussions with more than one big pharma regarding licencing deals.
Efficacy and safety of dendrimer-enhanced (DEP) cabazitaxel (CTX-SPL9111) in men with metastatic castration-resistant prostate cancer (mCRPC) in a phase I/II trialPresentation Number1403P
Speakers:
Robert H. Jones (Cardiff, United Kingdom)DateSun, 11.09.2022
AbstractBackground:
Dendrimers enable sustained delivery of cytotoxic drugs and achieve selective tumour targeting via an enhanced permeability and retention effect. DEP cabazitaxel is a lysine-based dendrimer modified with polyethylene glycol and with cabazitaxel attached to lysine branches via a hydrolysable linker. Unlike standard cabazitaxel, DEP cabazitaxel is highly water soluble, does not contain toxic excipients associated with anaphylaxis and avoids the need for steroid pre-medication. Safety and preliminary efficacy of DEP cabazitaxel was assessed in a phase 1/2 trial of with patients (pts) with advanced solid tumours, including mCRPC.
Methods:
3-weekly intravenous dosing of pts was escalated to study the safety profile and identify a recommended phase 2 dose (RP2D) for an expansion cohort. Eligible prostate pts had one or more of rising PSA, measurable disease progression, or bone progression per Prostate Cancer Working Group 3 (PCWG3) guidelines. Anti-tumour activity was assessed using these 3 PCWG3 criteria.
Results:
A RP2D of 20 mg/m2 cabazitaxel was confirmed; 2 Dose Limiting Toxicities of Grade 3 febrile neutropenia and grade 4 neutropenia > 7 days were observed. Most common toxicities were Grade 1/2 and those typically observed with standard cabazitaxel. There was no neutropenic sepsis or anaphylaxis. 25 mCRPC pts were enrolled at the RP2D; median age of 73 yrs and with an average 4 prior anticancer treatments, including taxanes. Responses were seen in one or more of the efficacy outcomes for all (100%) evaluable mCRPC pts. Of those evaluable for all PCWG3 criteria 56% responded in all three. In pts with soft tissue lesions, 64% had prolonged disease control, including 2 partial responses sustained for up ≥24 weeks. Of pts with assessable PSA, 90% had a reduction, with a response of >50% in 52%. Of pts with bone metastases, 83% had no progression or an improvement.
Conclusions:
DEP cabazitaxel is well tolerated with rates of severe myelosuppression, including neutropenia, lower than published data for standard cabazitaxel. No steroid pre-medication was required. We report encouraging anti-tumour activity in heavily pre-treated mCRPC pts.
(20min delay)
