Amsterdam, The Netherlands, June 6, 2019 - Kiadis Pharma N.V. ("Kiadis" or the "Company") (Euronext Amsterdam and Brussels: KDS), a clinical stage biopharmaceutical company, today announces that it has closed the previously announced acquisition of CytoSen Therapeutics, Inc. ("CytoSen").

The transaction creates a leader in cell-based cancer immunotherapy with proprietary and synergistic NK-cell and T-cell therapy platforms that have the potential to revolutionize HSCT and create a pipeline with novel cancer treatments. Kiadis now has a complementary development pipeline focused on improving outcomes for patients undergoing hematopoietic stem cell transplants (HSCT) with a T-cell therapy (ATIR101; in EU registration and a global Phase 3 clinical trial) and a NK-cell therapy (CSTD002; expected to enter the clinic in the US in 2020).

Arthur Lahr, CEO of Kiadis commented: "Our vision is to leverage the strengths of the human immune system to help patients with life-threatening diseases and through this acquisition we can now create novel cell therapies that combine the innate and adaptive arms of the immune system. This transaction is transformative for Kiadis as we now have two synergistic proprietary cell-based immunotherapy platforms and the ability to create a pipeline of innovative treatments for cancer patients."

Total upfront consideration paid to the holders of CytoSen shares and options on closing consists of 1,513,052 newly issued Kiadis shares and 159,778 options to acquire Kiadis shares. Upon acceptance by aforementioned parties of the shares issued to them, the newly issued Kiadis shares shall be admitted to trading on Euronext Amsterdam and Euronext Brussels on the basis of the listing prospectus within the meaning of Directive 2003/71/EC, as amended and Directive 2010/73/EU consisting of the registration document approved by the Netherlands Authority for the Financial Markets (Autoriteit Financiële Markten, "AFM") dated May 31, 2019 and the summary and securities note approved by the AFM dated May 31, 2019 that have been made generally available. Of the 1,513,052 newly issued Kiadis shares, 874,129 shares (57.8%) are subject to lock-up restrictions during a two-year period, and the other 638,923 shares (42.2%) are subject to lock-up restrictions during a 180-day period.

Further to the abovementioned 1,513,052 newly issued Kiadis shares, the holders of CytoSen shares have a conditional entitlement to receive 267,012 newly issued Kiadis shares - the Holdback Shares as defined in the listing prospectus. The Holdback Shares serve as a source for the satisfaction of indemnification and other claims that Kiadis may have on the CytoSen shareholders pursuant to the acquisition agreement. Subject to reduction in respect of these indemnification and other claims, the Holdback Shares will be issued 18 months from the completion date. Also, as per the acquisition agreement, the holders of CytoSen shares and options are eligible to potential future consideration of up to 5,819,460 additional Shares upon the achievement of six clinical development and regulatory milestones.

About ATIR101 and CSTD002
Administered as adjunctive immunotherapeutics on top of HSCT, ATIR101 and CSTD002 provide a lymphocyte infusions with functional, mature and potent immune cells from a haploidentical family member. The T-cells in ATIR101 and NK-cells in CSTD002 will help fight infections and remaining tumor cells, until the immune system has fully re-grown from stem cells in the transplanted graft. In addition, CSTD002 has shown promise in the treatment of relapse/refractory AML.

In ATIR101, T-cells that would cause GVHD are depleted from the donor lymphocytes, using our photodepletion technology. At the same time, ATIR101 contains potential cancer-killing T-cells from the donor that could eliminate residual cancer cells and help prevent relapse of the disease.

In CSTD002, nanoparticle processing technology enables improved ex vivo expansion and activation of NK-cells supporting multiple high-dose infusions with potent anti-cancer cytotoxicity.

About Kiadis
Founded in 1997, Kiadis Pharma, is a fully integrated biopharmaceutical company committed to developing innovative therapies for patients with late-stage blood cancers. With headquarters in Amsterdam, the Netherlands, and offices and activities in the US and across Europe Kiadis Pharma is reimagining medicine by leveraging the natural strengths of humanity and our collective immune system to source the best cells for life.

Kiadis Pharma is listed on the regulated market of Euronext Amsterdam and Euronext Brussels since July 2, 2015, under the symbol KDS. Learn more at kiadis.com.

Kiadis Contacts:

Kiadis Pharma:
Maryann Cimino, Manager, Corporate Affairs
Tel: +1 (617) 710-7305
m.cimino@kiadis.com

 
Optimum Strategic Communications:
Mary Clark, Supriya Mathur, Hollie Vile
Tel: +44 203 950 9144
David Brilleslijper (Amsterdam)
Tel: +31 610 942 514
kiadis@optimumcomms.com

Forward Looking Statements
Certain statements, beliefs and opinions in this press release are forward-looking, which reflect Kiadis Pharma's or, as appropriate, Kiadis Pharma's directors' current expectations and projections about future events. By their nature, forward-looking statements involve a number of risks, uncertainties and assumptions that could cause actual results or events to differ materially from those expressed or implied by the forward-looking statements. These risks, uncertainties and assumptions could adversely affect the outcome and financial effects of the plans and events described herein. A multitude of factors including, but not limited to, changes in demand, regulation, competition and technology, can cause actual events, performance or results to differ significantly from any anticipated development. Forward-looking statements contained in this press release regarding past trends or activities should not be taken as a representation that such trends or activities will continue in the future. As a result, Kiadis Pharma expressly disclaims any obligation or undertaking to release any update or revisions to any forward-looking statements in this press release as a result of any change in expectations or any change in events, conditions, assumptions or circumstances on which these forward-looking statements are based. Neither Kiadis Pharma nor its advisers or representatives nor any of its subsidiary undertakings or any such person's officers or employees guarantees that the assumptions underlying such forward-looking statements are free from errors nor does either accept any responsibility for the future accuracy of the forward-looking statements contained in this press release or the actual occurrence of the forecasted developments. You should not place undue reliance on forward-looking statements, which speak only as of the date of this press release.