Oracle 21c

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CREATE TABLE table1
    ("data" varchar2(15))
;

INSERT ALL 
    INTO table1 ("data")
         VALUES ('000000001 ItemA')
    INTO table1 ("data")
         VALUES ('000000002 ItemB')
    INTO table1 ("data")
         VALUES ('000000003 ItemC')
SELECT * FROM dual
3 rows affected

SELECT REGEXP_REPLACE("data", '^[0-9-]*\s', '') FROM table1;

REGEXP_REPLACE("DATA",'^[0-9-]*\S','')

ItemA

ItemB

ItemC

SELECT REGEXP_REPLACE("data", '^[[:digit:]-]*\s', '') FROM table1;

REGEXP_REPLACE("DATA",'^[[:DIGIT:]-]*\S','')

ItemA

ItemB

ItemC