MNTA has never been fully valued, IMO so I wouldn't be surprised if that continued. The way that enox played out is a cautionary tale to any crazy valuations, and is a powerful enough painful memory to give even perma bulls pause when contemplating going all in, even at this seemingly attractive valuation
RGLS is another one. Interesting technology but years away from any approval. Nevertheless, it popped last fall and is valued similarly to MNTA in terms of pps. Seems destined to make some people unhappy for a time.