Nginx reverse proxy configuration

Question

I need nginx to reverse- proxy GET and POST requests of the form:

/myapp/path/to/resource

to:

http://127.0.0.1:9090/path/to/resource

I'm trying the following:

location /myapp/(.*) { rewrite $1; proxy_pass http://127.0.0.1:9090; }

but nginx is returning a HTTP 405 error [not allowed].

Any ideas on how to fix this ? Thanks.