The study evaluates the efficacy and safety of allogeneic platelet lysate eye drops in patients with severe ocular graft versus host disease refractory to conventional systemic and local treatments. The corneal staining, conjunctival hyperemia, tear film break up time,Schirmer test and ocular surface disease index will be evaluated before and after allogeneic platelet lysate treatment. The safety of allogeneic platelet lysate treatment will be also assessed.

The corneal staining with fluorescein will be assessed using Oxford grading scale.

Tear film break up time is the time in seconds taken to appear first dry sport after complete blinking. Fluorescein is instilled into the patient tear film, the tear film is observed under cobalt blue illumination.Schirmer test will be performed without anesthesia. Conjunctival hyperemia will be graded from 0 to 2. The OSDI questinnaire will assess the impact of treatment on the quality of life.

Inclusion Criteria:

• Severe ocular chronic graft-versus-host disease (keratoconjunctivitis sicca) after allo-HSCT
• Schirmer test < 5mm\5min
• Tear Film Break-up Time < 5sec
• Corneal staining > II Gr (Oxford grading scale)
• Ocular Surface Disease Index (OSDI) >30
• Resistance to conventional therapy

Exclusion Criteria:

• Karnofsky <30%
• Other concomitant conditions, which does not allow to adequately assess the condition of the eye surface;
• Acute bacterial, viral or fungal infection of the eyes at the time of screening;
• Somatic or mental pathology that does not allow you to sign an informed consent;
• Keratoconjunctivitis sicca associated with an anomaly of the eyelids.

The individual participant data will be available upon request to the Pavlov Ethical Committee with the description of purposes and study plan according to local standard operating procedures.

15 years

The individual participant data will be available upon request to the Pavlov Ethical Committee with the description of purposes and study plan according to local standard operating procedures.