I think "reasonable" is doing a lot of heavy lifting here. Whatever price they charge it will be to maximize to Moderna's profits - i.e. they'll price it slightly lower than what insurers / national health systems would be stung for what 44% of melanoma patients needing a second round of expensive chemo would cost them but not so high that no one will cover the treatment. So I guess the price is "reasonable", in that it'll be cheaper than the alternative but it's not like Moderna will be charitable or fair about it.
It's still an amazing breakthrough though.
I actually got off my arse and did some productive programming over the Christmas break. Spent too long vegetating in front of the computer watching YouTube vids or playing games.