Proxy Apache FastCGI

Question

I have a domain with a python django application and the request tracker software. The goal of the post is to move the request tracker to the path "^/ ticket /*"

That's why the consideration is "mod_proxy_fcgi" (or does one rather use "mod_proxy_http"?).

Original working 000-default.conf code without proxy:

<VirtualHost *:80>
    DocumentRoot /opt/rt4/share/html
    Alias /NoAuth/images/ /opt/rt4/share/html/NoAuth/images/
    ScriptAlias / /opt/rt4/sbin/rt-server.fcgi/
    <Directory "/opt/rt4/sbin">
        Require all granted
    </Directory>
</VirtualHost>

Changed code with proxy settings (does not work):

<VirtualHost *:80>
    ProxyPassMatch "^/ticket/*" "fcgi://localhost:80/opt/rt4/sbin/rt-server.fcgi/"
    Alias /NoAuth/images/ /opt/rt4/share/html/NoAuth/images/
    ScriptAlias / /opt/rt4/sbin/rt-server.fcgi/

    <Directory "/opt/rt4/sbin">
        Require all granted
    </Directory>
</VirtualHost>

The proxy redirect returns HTTP code 503 "Service Unavailable" (http://localhost/ticket/).

Where am I wrong?