Ziarco gears up for Series C, PhIIb to advance atopic dermatitis drug

Discovery Park, Sandwich

Ziarco Pharma, a biotech birthed in Pfizer’s ($PFE) exit from Sandwich, is preparing to move its atopic dermatitis drug into Phase IIb. The commitment to advance the program, which follows the release of top-line data from a Phase IIa trial, has prompted Ziarco to begin talks about a Series C round that is expected to add new backers to the company’s A-list roster of investors.

Sandwich, U.K.-based Ziarco got started in 2012 when a team at Pfizer snagged some assets from their employer and struck out on their own. A $33.1 million (€29.5 million) Series B round followed in 2014. The money enabled Ziarco to run a 98-person Phase IIa trial of ZPL-389, an oral small molecule, selective histamine H4 receptor antagonist, in patients with moderate-to-severe atopic dermatitis, a condition more commonly known as eczema.

The study missed its primary endpoint of improvement in Numerical Rating Scale for pruritus, the medical term for severe itching, although Ziarco Executive Chairman Mike Grey told FierceBiotech a “meaningful reduction” was seen. Full data are due for publication at a conference next month. More positively, the trial hit its secondary endpoint of change to the Eczema Area and Severity Index (EASI) score. EASI was down 50% in the treatment arm, compared to 27% among patients who received the placebo.

When paired to safety and tolerability results that are comparable across the treatment and placebo arms, the readout adds up to a dataset Ziarco thinks justifies the advance of the program. “There's a clear clinical signal here and a clear signpost as to where to go next with this program,” Grey said. That next step will be a Phase IIb program, using EASI as the primary endpoint, that is due to get underway later this year.

As it stands, Grey expects to enroll around 300 people in the study across four arms, giving Ziarco the chance to gather data on three doses of ZPL-389 and compare them to the readout from a placebo group. The Phase IIa only looked at one dose of ZPL-389. Grey is also planning to gather data for longer than in the Phase IIa, the trends in which was yet to plateau when the study wrapped up after eight weeks of treatment. The Phase IIb will run for 12 weeks. “Obviously we want to see whether with longer treatment we could get additional effects,” Grey said.

Ziarco plans to run the Phase IIb trial in parallel to the CMC work it needs to carry out if it is to hit its target of having ZPL-389 ready for Phase III by the first quarter of 2018. Collectively, this work is beyond the current financial means of Ziarco, which last raised cash in a $33.1 million Series B round late in 2014. Amgen ($AMGN), Lundbeckfond Ventures, New Enterprise Associates and Pfizer all participated in the Series B.

Now, Ziarco has begun initial discussions with new investors. “We've got a great group of existing investors but would also look to bring in some new money around a Series C financing later in the year,” Grey said.

The Series C round is intended to ensure Ziarco has the financial means to execute its development strategy solo, but it isn’t ruling out a deal. With Regeneron ($REGN) and Sanofi’s ($SNY) dupilumab receiving blockbuster forecasts on the back of Phase III data and Pfizer paying $5.2 billion to get its mitts on Anacor Pharmaceuticals’ ($ANAC) crisaborole, Ziarco is well aware of the level of interest now being shown in atopic dermatitis.

That interest will translate into competition if ZPL-389 ever wins approval, but Grey spys a gap in the market for the drug. As an injectable biologic, Regeneron and Sanofi’s dupilumab is viewed by Grey as catering to patients with severe atopic dermatitis, although it was also trialled in people with moderate forms of the condition. Anacor’s crisaborole, in contrast, is in front of FDA as a treatment for mild-to-moderate atopic dermatitis. As Grey sees it, that leaves a window for an oral formulation that can treat patients with moderate-to-severe atopic dermatitis.

“There's a high degree of interest in that patient population ... and a high degree of interest in the program,” Grey said. That interest could bring Ziarco to the deal table. “While our intention is to continue to move the program forward in development, there is interest from outside. If there was the right level of interest, then we may take an alternative course,” he said.