Friday it was announced the European Commission has granted orphan drug status for Arenegyr, an anti-tumor therapeutic drug manufactured by MolMed S.p.A. in the treatment of malignant pleural mesothelioma (MPM).

According to PharmaLive, Arenegyr is a vascular targeting agent with a unique mode of action, and a first-in-class compound in the class of peptide/cytokine complexes able to selectively target the tumor vasculature. Unique biological properties include induction of tumor vascular permeability and normalization, and a direct biological anti-tumor activity.

PharmaLive quotes MolMed’s president and CEO, Claudio Bordignon, as saying, “Orphan drug designation for Arenegyr in mesothelioma represents a fundamental acknowledgement of the interesting early efficacy and safety results achieved in an ongoing Phase II trial, with 53 patients recruited so far, and which we just presented at the ASCO (American Society of Clinical Oncology) Annual meeting 2008.

He went on to say, “The analysis of preliminary study results presented at ASCO, conducted on 41 patients, already gave evidence of substantial clinical benefits in terms of long-lasting disease control and promising survivals in chemo-pretreated mesothelioma patients. In particular, it shows improved overall survival, and nearly doubled progression-free survival with respect to best supportive care data reported in literature.”

Bordignon said consolidated results relating to survival data will be available in December.

On April 21 I reported that a Madison, Wisconsin-based biotechnology firm, Quintessence Bioscience, was moving forward on a drug similar to Alfacel’s Onconase, to treat mesothelioma. The report, from Steve Clark for WTN (Wisconsin Technology Network) News, noted that the company’s QBI-139 is very similar to Onconase, but has not been clinically tested yet.

Of course, on Monday this week, it was announced and reported here that Onconase had failed the primary objective of its late-stage trial. This news was particularly disappointing since the drug already has orphan drug status in the U.S., Europe and Australia due to the very high hopes for its success. Despite failing in its primary objective, however, testing did show that the drug is effective in a secondary effect, helping to prolong the life of those treated after standard chemotherapy has failed.

The report of Onconase’s initial failure prompted WTN’s Clark to revisit Quintessence to find out if the Onconase failure would derail the development of their QBI-139. In his new report, Clarks says he found researchers undaunted and pressing forward. He says they hope to move the drug into clinical trials sometime this summer, and they believe the success of Onconase’s secondary role and hopeful FDA approval in that area will help pave the way for general acceptance of RNase cancer therapies.

In his earlier report, Clark pointed out that QBI-139 has several differences from Onconase in the way it is produced, which he believes will make it inherently more effective than Onconase.

He points out that mesothelioma is a particularly difficult cancer to treat, and wonders if the selection of mesothelioma as a research track by Alfacell was made to help fast-track the development of the drug. Perhaps, he wonders, the drug might be more effective on “more common and easier to treat cancers than mesothelioma.”