Remestemcel-L

RYONCIL is indicated for the treatment of steroid refractory acute graft versus host disease (SR-aGvHD) in pediatric patients 2 months of age and older. RYONCIL is an allogeneic bone marrow-derived mesenchymal stromal cell (MSC) therapy indicated for the treatment of steroid-refractory acute graft versus host disease (SR-aGvHD) in pediatric patients 2 months of age and older.

RYONCIL is available as a cell suspension for intravenous infusion in a target concentration of 6.68 X 10 6 MSCs per mL in 3.8 mL at cryopreservation contained in a 6 mL cryovial. Each 6 mL cryovial contains approximately 25 x 10 6 MSCs. Cryopreserved MSCs are combined with Plasma-Lyte ® A for administration. RYONCIL is available as a cell suspension for intravenous infusion in a target concentration of 6.68 X 10 6 MSCs per mL in 3.8 mL contained in a 6 mL cryovial.

Do not use RYONCIL in patients with known hypersensitivity to dimethyl sulfoxide (DMSO) or porcine and bovine proteins. Known hypersensitivity to dimethyl sulfoxide (DMSO) or Porcine and Bovine proteins. ( 4 )

Hypersensitivity/Acute Infusion reactions : Monitor for hypersensitivity reactions during infusion and premedicate with corticosteroids and antihistamines. ( 5.1 ) Transmission of Infectious Agents: RYONCIL may transmit infectious agents. ( 5.2 ) Ectopic Tissue Formation: Ectopic tissue formation may occur following treatment with RYONCIL. ( 5.3 )

5.1 Hypersensitivity and Acute Infusion Reactions Hypersensitivity reactions including acute infusion reactions have occurred with RYONCIL administration [see Adverse Reactions (6.1) ] . Serious hypersensitivity reactions, including anaphylaxis, may occur due to DMSO and trace amounts of porcine or bovine proteins. Signs and symptoms may include fever, dyspnea, and hypotension during or after RYONCIL infusion. Premedicate patients with antihistamine and corticosteroids and monitor closely for signs and symptoms of hypersensitivity or acute infusion reactions. If a hypersensitivity or infusion reaction occurs, interrupt RYONCIL infusion. Do not administer RYONCIL in patients who experience serious or life-threatening reactions.

5.2 Transmission of Infectious Agents Transmission of infectious disease or agents may occur with RYONCIL administration because it contains cells from human donors and is manufactured using human, porcine and bovine-derived reagents. Donors are screened and tested for Human Immune-deficiency Virus 1 (HIV-1); Human Immune-deficiency Virus 2 (HIV-2); Hepatitis B Virus (HBV); Hepatitis C Virus (HCV); Human T-cell Leukemia-lymphoma Virus 1 (HTLV-1); Human T-cell Leukemia-lymphoma Virus 2 (HTLV-2); West Nile Virus (WNV); Cytomegalovirus (CMV); Epstein-Barr Virus (EBV); and Syphilis ( Treponema pallidum ). Only screening was performed for Creutzfeldt-Jakob disease (CJD) and communicable disease risks associated with xenotransplantation. RYONCIL cell banks are tested for human and animal viruses, retroviruses, bacteria, fungi, yeast, and mycoplasma. Human and animal-derived reagents are tested for human and animal viruses, bacteria, fungi, and mycoplasma before use. These measures do not eliminate the risk of transmitting these or other infectious diseases or agents.

5.3 Ectopic Tissue Formation Ectopic tissue formation may occur following treatment with RYONCIL due to the ability of human mesenchymal stromal cells to differentiate into mesenchymal lineage cells such as bone, cartilage and fat cells.

The most common non-laboratory adverse reactions (incidence ≥20%) are: viral infectious disorders, bacterial infectious disorders, infection – pathogen unspecified, pyrexia, hemorrhage, edema, abdominal pain and hypertension ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Mesoblast at toll-free phone #1-844-889-MESO (6376) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1 Clinical Trials Experience Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice. The safety data described in this section reflect exposure to RYONCIL in 54 patients in Study MSB-GVHD001 for the treatment of SR-aGvHD. Patients received intravenous infusion of RYONCIL at a dosage of 2 x 10 6 MSCs/kg twice a week for four consecutive weeks, for a total of eight infusions. Patients with partial or mixed response at Day 28 received additional infusions of RYONCIL 2 x 10 6 MSCs/kg once a week for an additional four weeks [see Clinical Studies (14) ] . The median number of doses administered were 10 (range 1 to 16), and the treatment was administered over a median of 43 days (range 1 to 104 days). Serious adverse reactions occurred in 35 patients (65%) including pyrexia (n=5;9%), respiratory failure (n=5;9%), pneumatosis intestinalis (n=4;7%) and staphylococcal bacteremia (n=2;<5%). Eight patients had discontinuation of RYONCIL treatment due to the following: acute infusion reactions (n=3), hypotension (n=1), gastroenteritis (n=1), and death (n=3). Table 2 summarizes most common adverse reactions that occurred in ≥10% patients in Study MSB-GVHD001. Table 2: Adverse Reactions** Occurring in ≥10% of Patients in Study MSB-GVHD001 (N=54) a Based on National Cancer Institute Adverse Event Common Toxicity Criteria version 4.03 b No grade 4 or 5 adverse reactions occurred in the study *Is a composite that includes multiple related terms **Includes adverse reactions up to 100 days following RYONCIL treatment Adverse Reactions All Grades a n (%) Grade 3 b n (%) Viral infectious disorders* 30 (56) 8 (15) Bacterial infectious disorders* 24 (44) 10 (19) Infections – pathogen unspecified* 22 (41) 8 (15) Pyrexia 19 (35) 2 (4) Hemorrhage* 15 (28) 4 (7) Edema* 12 (22) 1 (2) Abdominal pain 11 (20) 4 (7) Hypertension 11 (20) 3 (6) Vomiting 10 (19) 3 (6) Arrhythmia* 9 (17) 2 (4) Diarrhea 9 (17) 1 (2) Rash* 9 (17) 0 (0) Arthralgia 8 (15) 0 (0) Fungal infectious disorders* 8 (15) 2 (4) Hypotension 8 (15) 2 (4) Cough 7 (13) 0 (0) Respiratory Failure 6 (11) 6 (11) Table 3 presents the most common grade 3 or 4 laboratory abnormalities that worsened from baseline in ≥10% of patients Table 3: Grade 3 or 4 Laboratory Abnormalities that Worsened from Baseline in ≥ 10% of Patients in Study MSB-GVHD001 (N=54) Laboratory Parameter Grade 3 or higher a % a Based on National Cancer Institute Adverse Event Common Toxicity Criteria version

4.03 Gamma-glutamyl transferase increased 32 Thrombocytopenia 28 Blood bilirubin increased 11

8.1 Pregnancy Risk Summary There are no available data for RYONCIL use in pregnant women. No animal reproductive and developmental toxicity studies have been conducted with RYONCIL to assess whether it can cause fetal harm when administered to a pregnant woman. It is not known if RYONCIL has the potential to be transferred to the fetus. Therefore, RYONCIL is not recommended for women who are pregnant. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 10-20%, respectively.

8.2 Lactation Risk Summary There is no information regarding the presence of RYONCIL in human milk, the effect on the breastfed infant, and the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for RYONCIL and any potential adverse effects on the breastfed infant from RYONCIL or from the underlying maternal condition.

8.4 Pediatric Use The safety and effectiveness of RYONCIL for treatment of SR-GvHD have been established in pediatric patients 2 months of age and older. The use of RYONCIL in these age groups is supported by evidence from an adequate and well-controlled trial [see Adverse Reactions (6) and Clinical Studies (14) ] .

The mechanism of action for RYONCIL is not clear but may be related to immunomodulatory effects. Data from in vitro studies demonstrate that MSCs inhibit T cell activation as measured by proliferation and secretion of pro-inflammatory cytokines. Acute GvHD occurs when alloreactive donor-derived T cells within the donated tissue (graft) trigger an immunological response, and alloreactive donor-derived T cells play a role in mediating the systemic inflammation, cytotoxicity and potential end organ damage associated with aGvHD.