Celyad : doses first AML patient at final dose level in CYAD-01 THINK trial and treats first patient with second cycle of therapy

• Celyad advances THINK trial to third and final dose level in hematological study arm
• Second cycle treatment amendment in THINK protocol approved and first patient dosed

'The observed tolerability profile of CYAD-01 to date as a stand-alone administration, along with the signs of clinical activity observed in relapsed refractory AML, highlight its potential for further development for both hematological cancers and solid tumors,' said Dr. Christian Homsy, CEO of Celyad. 'We have started administering the third dose level of CYAD-01 in a relapsed refractory AML patient in the THINK trial with no toxicity observed after the first injections. We look forward to completing the dose-escalation segment of the study, and, potentially an expansion phase, and reporting on the interim results of the THINK trial later this year at scientific congresses. In addition, we are happy to report that the first patient to receive a second cycle of CYAD-01 has been injected earlier this month.'

The open label Phase 1 THINK trial is being conducted in the US and in Europe. The dose-escalation segment, conducted in parallel in solid cancers and in hematologic cancer groups, includes three dose levels: 3x10⁸, 1x10⁹ and 3x10⁹ CYAD-01 cells per dose. At each dose level, the patients receive three successive administrations, two weeks apart, of CYAD-01 at the specified dose.

We expect that a total of three AML patients will receive the third and final, highest dose level. To date in the THINK trial, CYAD-01 has already shown signs of clinical activity at lower doses in AML patients who have received one cycle of CYAD-01 treatment per protocol ranging from complete response to stable disease. Celyad previously reported the world's first complete response by a CAR-T cell therapy, without pre-conditioning, in a patient with refractory and relapsed AML.

Based on the promising signs of activity observed to date, Celyad has started to evaluate if a second cycle of administration of CYAD-01 could improve or prolong the clinical responses. A first patient at the second dose level has successfully started his second cycle of treatment without any toxicity observed to date.

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