(HSP 90) Progress report on Mycograb from Neutec's results announcement:
The Company's lead product, Mycograb(R), is a genetically recombinant antibody ('grab') which binds to the immunodominant antigen, heat shock protein 90 (' hsp90'). The drug is based on a naturally-occurring human antibody response against hsp90, which facilitates the body in defending itself against life threatening infections. Hsp90 was recently highlighted in a leading journal as enabling pathogenic fungi to rapidly develop drug resistance whereas exposure to an hsp90 inhibitor, such as Mycograb(R), can enhance the effect of other anti-fungal agents and preclude or delay the onset of drug resistance or even reverse drug resistance. Also, earlier this month, Mycograb(R) was described as the only antifungal under development with a novel mechanism of action by a Task Force of the Infectious Diseases Society of America.
The evidence supporting the potential clinical and commercial value of Mycograb (R) in different clinical indications has continued to mount during the period under review. Mycograb(R) has made notable advances in each of the three clinical areas where its worth as an adjunct in combination with current best therapy is being assessed:
a) Invasive candidiasis
Following the impressive data from the confirmatory study for the treatment of invasive candidiasis reported upon in 2004, the Company prepared a Common Technical Document and filed an application for market authorization in March 2005. A number of GCP and GMP inspections were carried out by the Regulator in 2005 and at Day 120 in the process, the EMEA posed a number of questions to NeuTec. Detailed answers, often in the form of additional analyses, have been prepared and returned to the EMEA in respect of all questions received. The Company is currently awaiting the response to these answers.
In responding to the Regulator's questions, the drug's safety dataset has been significantly expanded: additional toxicological and pharmacokinetic data has been prepared and an additional voluntary phase I study was successfully carried out. Escalating doses of Mycograb(R) were given to allow for the definition of its safety profile, dose-proportionality, volumes of distribution, time dependent kinetics and method of elimination. This newly expanded dataset has facilitated a clearer label and a more defined set of application guidelines for the drug.
Progress with the Company's application for market approval remains within the EMEA's prescribed timelines and is consistent with a timetable that includes a regulatory decision before the year end.
Mycograb(R) has Orphan Drug Status in both Europe and the US in the treatment of invasive candidiasis. An editorial comment in Clinical Infectious Diseases (November 2005) concluded that earlier analyses have likely underestimated the true incidence of candidemia because of deficient diagnostic testing. The commentary went on to suggest that the attributable mortality rate associated with candidemia in a case control study in the US was estimated to be 49% and that hospital charges attributable to invasive candidiasis were $33,604 - $45,602 for adults and $65,058 - $119,474 for paediatrics per episode.
b) Carcinoma of the breast
The Company completed patient recruitment in its phase Ib, pharmacokinetic, multi-centre, open label study to evaluate the safety and efficacy of Mycograb (R) administered in combination with Docetaxel in metastatic or recurrent breast cancer patients in late 2005.
The primary objective of the study is to observe the safety and tolerability of Mycograb(R) in combination with Docetaxel when administered at twice the dosage used in the treatment of invasive candidiasis (ie at 2 mg per kg of body weight). The secondary objective is to monitor the response rate of the target tumours and overall survival and progression-free survival through seven months post treatment.
A total of 21 patients were recruited into the study and of these 7 patients have been withdrawn for the following reasons: withdrawal of patient consent (one patient), principal investigator decision (one patient), Docetaxel toxicity (three patients) and cancer progression (two patients). All 14 on-going patients have now received the full course of six cycles of treatment, three weeks apart, and all 20 surviving patients continue to be monitored on a regular basis.
Hsp90 has continued to attract significant industry and scientific attention as a prime target for combinatorial therapy against certain cancers. A presentation by the Company at the International Symposium on Targeted Anticancer Therapies (TAT) in March 2006 was well received and underlined the activity of the drug against a range of cancer cells in the laboratory.
c) Cryptococcal meningitis
Cryptococcus neoformans ('C. neoformans') is the most common form of fungal meningitis and is prevalent in patients with AIDS. It carries a mortality rate of up to 20%. NeuTec is about to commence a phase III study using Mycograb(R) in combination with current best therapy (generic amphotericin B and 5-flucytosine) against C. neoformans.
The trial will involve approximately 150 patients in a double-blind, placebo-controlled, multi-centre study. Regulatory and ethical approval has recently been obtained in South Africa and this follows a successful Investigational New Drug ('IND') application to the US Food and Drugs Agency (' FDA'). Hospitals in the United States, South Africa and South America have agreed to participate in the study and contracts with investigators are close to finalization.
The results from this trial will be used to assess the efficacy of Mycograb(R) against a further life threatening indication, will widen the safety database, particularly in a non-intensive care unit-based patient environment, and will explore the drug in combination with conventional amphotericin B (as used in the Japanese market in the treatment of systemic candidiasis) rather than liposomal amphotericin B (as used in the US and European markets for the treatment of invasive candidiasis).
Developmental programme
A total of eight patients have been included in the Company's compassionate use programme in England, Scotland, Belgium and the Netherlands, the majority having failed on mono-therapy with other drugs. As a result, Mycograb(R) has now been given in combination with conventional amphotericin B and Caspofungin as well as with liposomal amphotericin B. It has also been given successfully in the treatment of two children with invasive candidiasis. Significantly, this data has extended the patient safety database. The Company expects to commit further resource to this programme in the coming months.
Advisory group meetings have taken place which include a number of investigators who participated in the confirmatory study into invasive candidiasis and other experts in this area. A detailed programme for attending and presenting at major industry conferences and congresses is being followed, and this includes participation at the 2006 Meetings of the International Symposium on Intensive Care and Emergency Medicine (ISICEM) in Brussels, the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) in Nice and the International Society for Human and Animal Mycology (ISHAM) Congress in Paris.
These meetings form part of a wide-ranging programme for the identification and targeting of leading specialists and renowned clinicians in the treatment of severe fungal infection. They will extend the awareness of Mycograb(R) and its novel mechanism of action. This programme has been supplemented by the first technical publication of the mechanism of action entitled 'Fungal heat-shock proteins in human disease', published in FEMS (the Federation of European Microbiological Societies) in January 2006.
In order to comply with regulatory requirements regarding marketed drugs, the Company has been working with its principal Contract Manufacturing Organisation to implement a full Process Validation Programme during the summer. Three batches of Mycograb(R) were delivered during the period under review and contracts have been signed to secure a further 11 batches of drug in four campaigns over the next 18 months. |