Bioshares

Viralytics have positive reviews from Bioshare.

Advantages of CAVATAK CAVATAK has a number of advantages over Amgen's Imlygic. On some counts it performs consistently in line with Imlygic. Similar Overall Response Rate Phase II data from the two drugs showed that the overall response rate was similar, at 28% versus 26% in favour of CAVATAK.

Better Overall Durable Response Rate CAVATAK has a better durable response rate of 21% compared to 16% for Imlygic. However, it needs to be taken into account that Viralytics' data is only from a Phase II study. There is a difference in one year survival rates of 75% for CAVATAK compared to 58% for Imlygic.

CAVATAK – More Modes of Administration CAVATAK has the advantage over Imlygic in that it can be delivered through multiple modes of administration. It can be injected directly into the tumour, which is how Imlygic is delivered, and also be delivered through an intravenous injection (STORM study underway in UK) or intravesicular delivery (CANNON study underway in bladder cancer). Imlygic cannot be delivered in these other ways. CEO of Viralytics, Malcolm McColl, said at an investor meeting this week that patients are seropositive to the herpes virus, having been exposed to that virus previously, whereas with CAVATAK only 10% have been exposed to that virus (linked to the common cold) and those patients were screened out in clinical trials. McColl said that the tolerability for CAVATAK was excellent and that it is very selective, leaving healthy cells alone. CAVATAK has been shown to have an effect on distant tumours as well, with McColl showing images of reductions in lung tumours following CAVATAK delivery. “This is what causes death in patients,” said McColl, referring to the cancer metastases such as those in the lung. Viralytics will need to confirm the efficacy of its treatment in a Phase III trial. However the reality is that these drugs will likely be used as combination therapies with the new checkpoint inhibitors such as Yervoy, Optivo and Keytruda.

Combination Drug Trials Both Viralytics and Amgen are now conducting combination therapy trials with these new drugs and their respective oncolytic virus therapies. In February this year, Viralytics started a Phase Ib combination trial of CAVATAK in combination with Yervoy in 26 patients (MITCI study) with late stage melanoma. Last month Viralytics also commenced a Phase Ib study combining CAVATAK with Keytruda in 30 patients with late-stage melanoma (called the CAPRA study). The principal investigator of that study is Dr Howard Kaufman from the Rutgers Cancer Institute of New Jersey. McColl said Dr Kaufman is one of the leading clinicians in this field, who is highly recognised and was principal investigator in the Phase III Imlygic study. In early results from the Yervoy/CAVATAK combination study which is underway, McColl said that an almost complete response has been seen at 14 weeks, about which McColl said “you don’t see a Yervoy response this early.” With checkpoint inhibitors, it is not unusual to see the tumour in fact grow in size before the immune system starts to take effect. CAVATAK has been shown to change the tumour microenvironment, increasing the PDL1 levels on the tumour, which should make those tumours more susceptibly to the checkpoint inhibitor drugs. McColl said that checkpoint inhibitor drugs are anticipated to generate sales of US$24 billion by 2013. Viralytics is keen to share in some of that revenue expected to flow to the cancer immunotherapy drug class.

Recruitment Benefit of Immunotherapy Cancer Drugs McColl said that there is a lot of appeal to this new front of cancer therapy which harnesses the immune system, because it makes it very easy to recruit patients, compared to small molecule drugs in melanoma for which recruitment is much more difficult. The CAPRA trial, for instance, should be very easy to recruit patients also because the patients will get access to the new drug Keytruda. With the MITCI and CAPRA trials being open label, the company will be able to report data on patients as the trial progresses.

CANNON Bladder Cancer Study McColl said there is a desperate need for better treatments for bladder cancer, with current treatments being almost prehistoric. In this trial, in which the virus is introduced through intravesicular delivery, the virus is tracking to the tumour said McColl with viral replication. The results are looking good so far.

STORM IV Study in Solid Tumours In this intravenous delivery of the treatment, a reduction has been observed in prostate cancer, and the virus has moving to the melanoma cells. If it can fire up the immune response, then a combination treatment will work well believes McColl. McColl said that he is confident that Viralytics will be the second approved oncolytic cancer therapy. The other competitors to Viralytics are either at a much earlier stage of development than Viralytics or are bringing older programs back into development said McColl. Viralytics plans to initiate additional combination trials. Viralytics is capitalised at $106 million with $19.5 million in cash at the end of September. The company has cash sufficient to meet its requirements to the end of 2016.

It surely is worth the wait.