。
She insisted again and again that she was innocent.
Literal
She [topic-は] many-times self [topic-は] innocent is [quotative-と] repeated.
繰り返す ('repeat') paired with the quotative と and an embedded clause is the standard frame for 'repeatedly say/claim that ~.' 何度も intensifies the repetition: 'many times, again and again.' Note the embedded subject 自分 ('oneself') marked with は — the contrastive flavor here picks her out from any unstated alternatives ('whatever others might say, I am innocent'). 無実 ('innocence, blamelessness') is more specific than the broader 無罪 ('not guilty in a legal sense'), often used in self-defense or contested-accusation contexts.