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EPO Rejects Mirrx Bid to Reinstate Patent Proceedings Ahead of Ruling on Suit with Santaris


By Doug Macron

The European Patent Office this month handed Mirrx Therapeutics a major setback in its efforts to secure a patent on its core technology by ruling that it would not resume a review of an application covering the intellectual property until Mirrx concludes a legal dispute with Santaris Pharma over the technology.

As a result of the decision, Mirrx said it may have to wait as long as two years before it can secure the patent. During that span, the company said, it may be unable to secure additional investments needed to stay in business.

A spinout of Danish start-up Stealth Biotech, Mirrx is focused on developing and commercializing novel microRNA inhibitors called Blockmirs (GSN 2/4/2010). The agents, steric antisense oligos that bind to specific miRNA target sites, are meant to prevent the regulation of a particular messenger RNA.

Because they do not inhibit miRNAs themselves, Blockmirs are more specific than other miRNA antagonists and cause fewer off-target effects, according to Mirrx.

In 2009, Santaris Pharma sued Mirrx and its founder, Thorleif Moller, for allegedly misusing company trade secrets related to Santaris' locked nucleic acid technology to develop and file European patent applications on Blockmirs for therapeutic applications (GSN 5/6/2010).

As part of its legal strategy, Santaris successfully petitioned the EPO to halt all proceedings related to one of Mirrx's key patent applications, EP 07817970, until the lawsuit has been settled.

It's not the first time the agency handed Mirrx a no-go decision. About a year ago, the agency rejected the company's request to reinstate the proceedings, ruling that the Santaris litigation "is an entitlement dispute … and the balance of interests is not clearly in favor of the [intellectual property's] applicant in the sense that proceedings should be resumed" (GSN 8/26/2010).

Additionally, the EPO determined that its legal division is “neither competent nor qualified to decide which party the [patent] application might belong to or which outcome of the … dispute seems more likely.”

Still, the agency late last month gave Moller the opportunity to plead his case directly, although it was not swayed.

According to the patent office, Moller portrayed the situation between privately held Mirrx and publicly traded Santaris as a battle between “David and Goliath,” and stated that Mirrx is facing “extreme difficulty in raising funds” from investors scared off by the litigation.

Moller “stated that three companies were at present doing research in this field of technology and … emphasized the need to resolve the case quickly,” the EPO said, adding that Moller stressed that if the stay on the patent application were maintained, Mirrx might face liquidation being unable to secure additional investment funds.

The Danish court hearing the lawsuit — both companies are based in Copenhagen — is only expected to get to the Mirrx/Santaris case in about two years, he added.

Though Santaris agreed that it could take years before the case was settled in court, it stressed that “delaying tactics were not being used … and getting expert opinion was proving no easy task,” according to EPO.

EPO, siding with Santaris, said it found no evidence that Santaris is purposely attempting to drag out the dispute, adding that the estimated length of the litigation cannot be counted in Mirrx's favor.

“A financial impact of the stay of proceedings on [Mirrx] must be borne as an inherent consequence of the balance of rights” set forth by the EPO. “Consequently, patent grant proceedings are not resumed.”

With the EPO's ruling, it appears that Mirrx's only recourse is the Danish court system, with which it has already filed responses to Santaris' allegation that “the connection and overlap between Santaris Pharma's [locked nucleic acid] technology and … Moller's applications is so close that there is a presumption against them having been prepared … without knowledge of Santaris Pharma's confidential patent applications and the current research developments at Santaris."

In its suit, Santaris charged that Moller allegedly obtained access to the company's know-how when he worked as a consultant for the Danish patent firm Ploughmann & Vingtoft, which was Santaris' IP agent, and through his “cohabitating partner,” who formerly worked for Santaris.

For his part, Moller has long maintained that Blockmirs are fundamentally different from Santaris' LNA technology since they prevent a miRNA from binding to a single target, rather than all its targets.

Importantly, he claims that the lawsuit is merely an attempt by Santaris to gain control of a technology that would allow it to avoid infringing IP held by competitor Regulus Therapeutics related to the inhibition of miR-122 as a treatment for hepatitis C.

Santaris' LNA-based miR-122-targeting drug miravirsen is currently in phase II testing. Regulus, meanwhile, has its own miR-122 inhibitor in preclinical development through a collaboration with GlaxoSmithKline, along with the exclusive rights to US Patent No. 7,307,067, which covers the regulation of the miRNA as an HCV treatment

The intellectual property situation came to a head, Moller argued, when GlaxoSmithKline passed on an option to license miravirsen, instead choosing to partner with Regulus (GSN 2/25/2010).

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