XSS inside without the ‘

As a pentester i came across this scenario:

<script type="text/javascript">   URL = 'http://example.com?x=input'; 

I am able to insert a new line with %A0, spaces and almost anything except ‘ and the problem is that i need that ‘ before making a new line so the js doesn’t break and works.

i am able to leave it like this:

<script type="text/javascript">   URL = 'http://example.com?x=input;  prompt`9`  anything'; 

After the input and before the ; i need to insert a ‘ or it won’t work… is any workaround/bypass on this? i am able to inset / too.