It can happen in a New York minute. We are talking about the massive gains certain healthcare stocks are able to notch in what feels like a split second. Unlike names from other areas of the market, earnings results don’t paint the full picture. Rather, other factors like clinical trial data or regulatory decisions can be more useful in determining if a particular company is on the path to life-sustaining revenues. Therefore, any positive update can be the catalyst that sends shares blasting off towards outer space.These plays, however, aren’t without their risk. A disappointing outcome could also be the spark that ignites the flame, only launching shares in the opposite direction. This is what makes compelling healthcare stocks so difficult to spot, but the analysts can help.Using TipRanks’ database, we found three healthcare stocks getting love from the Street ahead of major possible catalysts. Each name has amassed enough bullish calls to earn a “Strong Buy” consensus rating. Hefty upside potential is also on the table here.Kala Pharmaceuticals (KALA)Developing treatments for inflammatory ocular conditions, Kala Pharmaceuticals wants to improve the lives of patients everywhere. With the October 30 PDUFA date for its EYSUVIS product fast-approaching, several analysts think that now is the time to get on board.EYSUVIS is a corticosteroid designed for the short-term treatment of signs and symptoms of dry eye disease (DED). DED is a multifactorial disease of the tears and ocular surface of the eye that causes discomfort, visual disturbances and tear film instability, which is usually accompanied by hyperosmolarity (higher concentration of salt than water in tears) and inflammation. Affecting about 16.4 million adults in the U.S., the condition has a major impact on a patient’s quality of life, and in some cases, can lead to declines in work productivity.Wedbush analyst Liana Moussatos is optimistic about the therapy’s prospects, noting that approval could come before the PDUFA date. To this end, a U.S. launch is forecasted for early 2021, with KALA set to be launch ready in Q4 2020, and the analyst believes blockbuster revenue ($1 billion) could be in store.Citing presentations from Key Opinion Leaders (KOLs), Moussatos highlights the broad market opportunity for the asset given the current unmet need and its potential position as the first approved corticosteroid in this indication.Additionally, based on clinical data, unlike already approved drugs RESTASIS, CEQUA and XIIDRA, the therapy generated a rapid onset of action, with it also overcoming well-known adverse events associated with ketosteroids such as increases in intraocular pressure (IOP).Moussatos mentioned, “Dr. Holland made specific reference in his remarks to both EYSUVIS’ rapid onset of action as well as its favorable safety profile with respect to IOP elevation as reason for his choice to use it as first-line therapy for a high percentage of his patients if approved.”Summing it all up, the analyst stated, “Given the inadequate control of dry eye flares on current standard-of-care treatments and the unwillingness of eye care professionals (except cornea specialists) to use corticosteroids off-label, we feel EYSUVIS is uniquely positioned to immediately address an underserved portion of the market using corticosteroids off-label as a short-term therapy for rapid relief while gradually addressing chronic users of immunomodulatory agents such as cyclosporine (RESTASIS, CEQUA) and lifitegrast (XIIDRA) on maintenance therapy.”To this end, Moussatos rates KALA an Outperform (i.e. Buy) along with a $39 price target. This puts the upside potential at a massive 430%. (To watch Moussatos’ track record, click here)In general, other analysts echo Moussatos’ sentiment. 4 Buys and 1 Hold add up to a Strong Buy consensus rating. With an average price target of $20.80, the upside potential comes in at 173%. (See KALA stock analysis on TipRanks)Revance Therapeutics (RVNC)Focused on innovative aesthetic and therapeutic offerings, Revance Therapeutics works to address the unmet needs of patients. As multiple catalysts are on the horizon, Wall Street is pounding the table.Investors are eagerly awaiting the FDA decision regarding RVNC’s novel botulinum toxin (BoNT) product, daxibotulinumtoxinA for Injection (DAXI), in glabellar (frown) lines. The PDUFA date is scheduled for November 25.Ahead of the decision, Guggenheim's Seamus Fernandez has high hopes. “Given the positive SAKURA results, our approval expectations are high,” the 5-star analyst commented.That being said, Fernandez argues “DAXI's potential in the therapeutic market is underappreciated, particularly for the upcoming ASPEN-1 results in cervical dystonia (CD),” which is a movement disorder that results in abnormal posture or twisting of the neck. This indication marks DAXI’s foray into the world of therapeutics, with the pivotal ASPEN-1 top-line data readout set to come by or before late-November. When it comes to DAXI in the CD indication, the asset’s long-acting profile makes it a stand-out compared to available BoNTs, which are short-acting. In a Phase 2 trial, DAXI demonstrated a duration of effect greater than 20-24 weeks at all doses, versus that of marketed BoNT toxins (12 weeks on average; ranges 12-18 weeks depending on the formulation or dose).“Payers have limited BoNT access to an every-12-week (Q12W) dosing schedule for CD. However, based on expert discussions, 20-25% of de novo CD patients complain of pain recurring prior to the next injection, and thus do not find relief from the existing insurance-mandated Q12W dosing schedule. DAXI could be an alternative BoNT for these patients. Moreover, DAXI had demonstrated a peak treatment effect of 50% in its earlier Phase 2 trial, which, in our view, is best-in-class,” Fernandez explained. To this end, substantial upside could be in the cards if RVNC reports positive data.If that wasn’t enough, the release of top-line results from its Phase 2 trial in plantar fasciitis (PF), a common cause of heel pain, is slated for the same timeframe. Roughly 2 million patients with the condition seek treatment annually, but the standard-of-care usually includes NSAIDs, orthotics, physical therapy, rest, weight loss or corticosteroids, with physicians trying to avoid excessive use of steroids.However, BoNTs, used off-label by some specialists due to success in small studies, have yet to succeed in a randomized Phase 2 or Phase 3 study. “Given the opportunity to differentiate itself from the existing BoNT therapeutic market, RVNC is conducting a second larger Phase 2 trial with 155 patients,” Fernandez noted. While his models don’t include PF, favorable results could be a game changer.Taking all of this into consideration, Fernandez maintains a Buy rating and $41 price target. This target conveys his confidence in RVNC’s ability to climb 65% higher in the next year. (To watch Fernandez’s track record, click here)Are other analysts in agreement? They are. Only Buy ratings, 5 to be exact, have been issued in the last three months. Therefore, the message is clear: RVNC is a Strong Buy. Given the $34.20 average price target, shares could surge 38% in the next year. (See RVNC stock analysis on TipRanks)Rhythm Pharmaceuticals (RYTM)Changing the way rare genetic disorders of obesity are diagnosed and treated, Rhythm Pharmaceuticals is developing cutting-edge therapies. As it gears up for key potential catalysts, the Street has its eye on this healthcare name.Back in May, the FDA accepted RYTM's new drug application for setmelanotide, the company’s melanocortin-4 receptor (MC4R) agonist, in pro-opiomelanocortin (POMC) and leptin receptor (LEPR) deficiency obesities. With a PDUFA date set for November 22, an approval decision is right around the corner.Ladenburg analyst Michael Higgins points out that after an update from management, his bullish thesis remains very much intact.RYTM revealed that once weekly dosing of setmelanotide achieved similar results to the daily formulation, with comparable weight loss among treated patients exceeding placebo. “This data could set up a label expansion for setmelanotide following approval and may be particularly advantageous for pediatric administration, who are often most afflicted by POMC and LEPR,” Higgins commented.The analyst is also watching out for data from the pivotal trial evaluating setmelanotide in Bardet-Biedl Syndrome (BBS) and Alström syndrome, with data expected in Q4 2020 or Q1 2021, and the Phase 2 Basket Study of setmelanotide in high-impact heterozygous (HET) obesity and other genetic disorders, which could be released in Q4 2020.In a recent journal article highlighting setmelanotide in BBS patients, the published data further highlights the success of BBS patients who are taking setmelanotide, as efficacy measures increase with prolonged use. Higgins sees the article as encouraging, given that it was written by several reputable KOLs.Higgins points out that this pivotal patient data set is at least twice the size of the POMC/LEPR Phase 3 trial, conveying the increase in the size of the market opportunity. There are roughly 250 POMC/LEPR patients in the U.S., compared to approximately 2,000 BBS/Alström patients. As for the basket study, Higgins estimates there are tens of thousands of patients with MCR pathway disorders.Given all of the above, Higgins stays with the bulls. In addition to a Buy rating, he puts a $43 price target on the stock. Investors could be pocketing a gain of 95%, should this target be met in the twelve months ahead. (To watch Higgins’ track record, click here)Judging by the consensus breakdown, opinions are anything but mixed. With 4 Buys and no Holds or Sells assigned in the last three months, the word on the Street is that RYTM is a Strong Buy. At $38.67, the average price target implies 75% upside potential. (See RYTM stock analysis on TipRanks)To find good ideas for healthcare stocks trading at attractive valuations, visit TipRanks’ Best Stocks to Buy, a newly launched tool that unites all of TipRanks’ equity insights.Disclaimer: The opinions expressed in this article are solely those of the featured analysts. The content is intended to be used for informational purposes only. It is very important to do your own analysis before making any investment.