new patent granted

US patent issued for DEP cabazitaxel nanoparticle
Melbourne, Australia; 15 September 2021: Starpharma (ASX: SPL, OTCQX:
SPHRY) today announced that the US Patent and Trademark Office has granted a new
patent in relation to DEP® cabazitaxel. The composition of matter patent builds on
Starpharma’s suite of existing international DEP® patents for the product. It specifically
covers a DEP® dendrimer conjugated to multiple cabazitaxel drug molecules via a
particular releasable linker, with a patent term to 2039 and the potential for a further 5
year extension. The DEP® cabazitaxel nanoparticle is currently in late phase 2 clinical
development, recruiting patients with solid tissue tumours, including prostate, ovarian
and gastro-oesophageal cancers.
DEP® cabazitaxel is a proprietary nanoparticle version of leading prostate cancer drug
cabazitaxel (Jevtana®), which had global sales of US$536 million in 2020.
DEP® cabazitaxel is an aqueous nanoparticle formulation which has a number of
advantages compared to the original formulation of cabazitaxel. DEP® cabazitaxel is a
water soluble, polysorbate-80 (detergent)-free formulation, with no requirement for
pre-treatment with steroids nor G-CSF to reduce the risk of severe bone marrow
toxicity. In both preclinical and clinical studies, DEP® cabazitaxel has shown an
improved side effect profile, notably markedly reduced bone marrow toxicity
demonstrated by lower rates of severe neutropenia, thrombocytopenia and severe
anaemia, which are all experienced by a significant proportion of patients treated with
Jevtana®.
Starpharma has completed a phase 1 trial of DEP® cabazitaxel in patients with solid
tissue tumours where efficacy signals were observed including in patients with
prostate, gastro-oesophageal, breast, ovarian, cholangiocarcinoma and pancreatic
cancer. Patients in the phase 1 trial were treated with up to 15 cycles of DEP®
cabazitaxel with no steroid, antihistamine or anti-emetic pre-treatment. Patients
experienced significantly lower levels of side effects commonly associated with
Jevtana® such as bone marrow toxicity (neutropenia, anaemia, thrombocytopenia)
anorexia and vomiting. There were no cases of hypersensitivity; no cases of hair-loss;
no need for anti-nausea medications.
Starpharma’s phase 2 trial of DEP® cabazitaxel is well advanced with more than 40
patients treated with multiple cycles of DEP® cabazitaxel in which the markedly
reduced rates of severe / life-threatening bone marrow toxicity and a lack of severe
hypersensitivity continues to be demonstrated. In the trial, encouraging efficacy signals
have been observed in multiple tumour types, including in prostate cancer where
radiological responses, significant reductions in prostate-specific antigen (PSA) and
no new bone metastases were observed. These encouraging efficacy signals were
observed despite patients having been heavily pre-treated - with an average of 30 prior
cycles of treatment, and in some cases with more than 100 cycles and up to 10
different treatment regimens. In addition to the responses described above in prostate
cancer, patients treated with DEP® cabazitaxel have also exhibited encouraging
2
efficacy signals in gastro-oesophageal, ovarian, cholangiocarcinoma, lung, and head
and neck cancers.
Starpharma Chief Executive, Dr Jackie Fairley, commented: “The grant of this new US
patent illustrates the unique and compelling benefits of Starpharma’s DEP® drug
delivery technology and DEP® cabazitaxel. We look forward to completing the phase 2
clinical program for DEP® cabazitaxel, in parallel with commercial discussions with
potential licensing partners.”
DEP® cabazitaxel was developed using the Company’s proprietary DEP® drug delivery
platform, which is being used by Starpharma and a number of partners to create novel
nanoparticle formulations of existing and new drugs to enhance both their therapeutic
and commercial value. DEP® drug delivery is applicable to a wide range of drugs, in
oncology (including radiopharmaceuticals and ADCs) and other therapeutic areas. In
addition to developing its own internal pipeline of DEP® assets, Starpharma has
several DEP® commercial partnerships with companies, including AstraZeneca, Chase
Sun and Merck & Co., Inc., to develop DEP® versions of their products or ADCs,
including AstraZeneca’s DEP® AZD0466, a Bcl2/xL inhibitor that is currently in clinical
development with a global trial in haematological tumours commencing earlier this
year.
About DEP®
Starpharma’s proprietary dendrimer-based DEP® platform has broad commercial
applicability in drug delivery by enhancing the therapeutic utility of drugs through
improved solubility, efficacy and pharmacokinetic control, reductions in certain
toxicities (e.g. bone marrow toxicity) and creating a unique intellectual property
position. The novel DEP® platform has shown reproducible advantages across a wide
range of drug classes and can be utilised with both small molecule drugs, peptides
and proteins, and in the development of unique DEP® based ADCs, radiotherapies and
radiodiagnostics.
Benefits of DEP® dendrimer drug delivery include:
• Improving efficacy
• Improving therapeutic index
• Reducing toxic side effects of drugs
• Enhanced and controllable pharmacokinetics
• Tumour targeting
• Increased aqueous solubility, avoiding the need for toxic excipients (e.g.
polysorbate-80) thus reducing the need for steroid pre-treatment
• Delivering a variety of payloads (small molecules, proteins, radio-isotopes)
• Creation of new intellectual property
Starpharma has three phase 2 clinical stage DEP® assets, multiple preclinical DEP®
programs, and has applied its DEP® technology in partnership with pharmaceutical
companies for many different applications (passive and targeted ADC and
radiotheranostics) and diseases (oncology and non-oncology applications)