MKM analyst Bill Kirk said Aurora Cannabis Inc. /zigman2/quotes/210559470/composite ACB -0.39% /zigman2/quotes/203734337/delayed CA:ACB -0.22% is not out of the woods yet, after the Canadian weed company posted better-than-expected fiscal third-quarter earnings last week. The stock has been on a tear for the last two sessions, is up 93% in the month to date and up another 14% in premarket trade Tuesday. Aurora beat revenue estimates and said it expects to have positive adjusted Ebitda in the first quarter of 2021. "With an uncertain revenue outlook, we don't yet have enough confidence in cost-cutting measures to rely on their 1Q'21 positive adjusted EBITDA goal," Kirk wrote in a note to clients. "If sequential growth slows/stalls (April/May worse than March), the best-case 1Q'21 gross profit dollars would be ~C$45mn, which would be more than fully offset by SG&A and R&D expenses (~C$60mn)." Despite cost-cutting efforts, Aurora's third-quarter sales, general and admin costs rose 21% from a year ago and outpaced sales growth of just 16%. Kirk said he also expects another C$1 billion in writedowns in the next quarter, when the company will retest its goodwill. "Finally, despite the efforts to streamline production, Aurora is still growing far more cannabis than it is able to sell (3Q: 36,207 kg grown vs. 12,729 kg sold; YTD: 108,334 kg grown vs. 34,693 kg sold)," said the note. "We don't see demand growth accelerating enough to consume this inventory and expect Aurora to ultimately write it down." The Cannabis ETF /zigman2/quotes/213173823/composite THCX -1.87% has fallen 23% in the year to date, while the S&P 500 /zigman2/quotes/210599714/realtime SPX +0.06% has fallen 9%.