Table 2.
Number of adverse events leading to discontinuation of prior conventional thiopurines
| Azathioprine (N) | Mercaptopurine (N) | Total (N) | |
|---|---|---|---|
| Gastrointestinal disorders | 50 | 42 | 92 |
| Nausea | 21 | 21 | 42 |
| Abdominal pain | 9 | 8 | 17 |
| Vomiting | 9 | 7 | 16 |
| Pancreatitis | 11 | 4 | 15 |
| Oral dysesthesia | 0 | 1 | 1 |
| Diarrhoea | 0 | 1 | 1 |
| Investigations | 25 | 19 | 44 |
| Liver function test increased a | 13 | 10 | 23 |
| White blood cell decreased | 5 | 5 | 10 |
| Alanine aminotransferase increased | 3 | 1 | 4 |
| Pancytopenia b | 1 | 2 | 3 |
| Aspartate aminotransferase increased | 2 | 0 | 2 |
| GGT increased | 0 | 1 | 1 |
| Weight gain | 1 | 0 | 1 |
| General disorders and administration site conditions | 13 | 12 | 25 |
| Malaise | 4 | 6 | 10 |
| Fever | 6 | 3 | 9 |
| Flu like symptoms | 3 | 0 | 3 |
| Edema limbs | 0 | 2 | 2 |
| Fatigue | 0 | 1 | 1 |
| Skin and subcutaneous tissue disorders | 8 | 8 | 16 |
| Rash (undefined) c | 4 | 5 | 9 |
| Alopecia | 2 | 2 | 4 |
| Pruritus | 1 | 1 | 2 |
| Eczema | 1 | 0 | 1 |
| Musculoskeletal and connective tissue disorders | 8 | 6 | 14 |
| Arthralgia | 5 | 2 | 7 |
| Back pain | 1 | 2 | 3 |
| Bone pain | 2 | 0 | 2 |
| Myalgia | 0 | 2 | 2 |
| Nervous system disorders | 6 | 6 | 12 |
| Headache | 3 | 3 | 6 |
| Hypersomnia | 3 | 3 | 6 |
| Infections and infestations | 0 | 2 | 2 |
| Upper respiratory infection | 0 | 2 | 2 |
| Epstein‐Barr virus infection reactivation | 0 | 1 | 1 |
| Folliculitis | 1 | 0 | 1 |
| Psychiatric disorders | 1 | 2 | 3 |
| Irritability | 1 | 1 | 2 |
| Insomnia | 0 | 1 | 1 |
| Other | 5 | 1 | 6 |
| Anemia (blood and lymphatic system disorders) | 4 | 1 | 5 |
| Hematomas (vascular disorders) | 2 | 0 | 2 |
| Unknown | 3 | 1 | 4 |
| Total | 121 | 100 | 221 |
Pooled adverse events according to Common Terminology Criteria for Adverse Events (CTCAE v5.0) of prior conventional thiopurine therapy (azathioprine or mercaptopurine). Some patients experienced multiple adverse events.
a
Increased value of ≥1 of the following: Alanine aminotransferase, aspartate aminotransferase, GGT, alkaline phosphatase, bilirubin.
b
Pancytopenia is defined as a decreased value of ≥1 of the following: Hemoglobin, white blood cells, thrombocytes.
c
Any skin condition involving erythema or other visual skin changes not specified in CTCAE.